Fact-checked by Grok 2 weeks ago

Intermittent fasting

Intermittent fasting (IF) is an eating pattern that cycles between periods of fasting, during which few or no calories are consumed, and periods of normal eating, typically lasting from 12 hours to several days.^[1] Unlike traditional diets that emphasize specific foods or calorie counts, IF focuses primarily on the timing of meals to influence metabolism and health outcomes.^[2] Common methods of IF include time-restricted feeding, such as the 16/8 approach, where individuals eat within an 8-hour window (e.g., noon to 8 p.m.) followed by 16 hours of fasting; alternate-day fasting, which alternates between days of normal calorie intake and days of severe restriction (often 500 calories or less); and the 5:2 diet, involving five days of unrestricted eating and two non-consecutive days of low-calorie intake (500–600 calories).^[1] These regimens trigger a "metabolic switch" after about 12–36 hours of fasting, shifting the body from glucose-based energy to fatty acids and ketones, which may promote fat burning while preserving muscle mass.^[2] Studies indicate potential benefits of IF for metabolic health, including significant weight loss (1.3% to 8.0% of body weight in trials lasting 2–24 weeks), improved insulin sensitivity, reduced fasting glucose and insulin levels, and lower levels of cholesterol (up to 32%), triglycerides (16–42%), and blood pressure (3–10%).^[3]^[2] These effects are attributed to mechanisms like enhanced autophagy, activation of pathways such as AMPK and SIRT1, and reduced inflammation, with evidence from human trials showing cardiometabolic improvements in overweight and obese adults over 8–24 weeks.^[2] Short-term IF has also been linked to better cognitive function, including executive function and memory, in some interventions.^[2] However, IF is not without risks, particularly for certain populations. Common side effects include hunger, irritability, fatigue, headaches, dizziness, constipation, and mood changes, especially during adaptation, affecting less than 15% of participants in trials but potentially exacerbating issues like disordered eating or menstrual irregularities.^[1]^[3] A preliminary analysis presented at the American Heart Association's 2024 Scientific Sessions found that an 8-hour time-restricted eating pattern was associated with a 91% higher risk of cardiovascular death compared to eating over 12–16 hours, though this requires peer-reviewed validation and may relate to factors like elevated stress hormones or adrenaline.^[4] IF is generally considered safe for healthy adults when supervised but is contraindicated for pregnant or breastfeeding individuals, those with eating disorders, diabetes (due to hypoglycemia risk), or a history of cardiovascular disease.^[1]^[4] Historically, IF has roots in religious practices like Ramadan and was explored medically as early as 1914 for conditions such as diabetes and epilepsy, with modern research building on caloric restriction studies since the 1930s.^[2] While promising for weight management and longevity in animal models, human evidence remains mixed, emphasizing the need for personalized approaches under medical guidance.^[3]^[2]

Overview

Definition

Intermittent fasting is an eating pattern that cycles between periods of voluntary abstinence from caloric intake and periods of unrestricted eating, with the primary emphasis placed on the timing of meals rather than the composition or quantity of food consumed.^[5] This approach encompasses various protocols, such as time-restricted feeding where eating is confined to a specific daily window, for example, the common 16:8 method involving 16 hours of fasting and an 8-hour eating period.^[6] Unlike traditional calorie restriction, which focuses on reducing overall energy intake through portion control or dietary limitations, intermittent fasting prioritizes the scheduling of eating episodes, although it may incidentally lead to lower total calorie consumption due to the shortened feeding windows.^[3] During fasting periods, typically ranging from 12 to 48 hours, individuals abstain from foods and caloric beverages but may consume non-caloric options such as water, unsweetened tea, or black coffee to maintain hydration.^[6] From an evolutionary perspective, humans have adapted to environments with irregular food availability, developing metabolic flexibility—the ability to efficiently switch between fuel sources like glucose and fats during fed and fasted states—which intermittent fasting mimics to promote physiological resilience.^[7] This adaptability underscores the pattern's alignment with ancestral patterns of feast and famine.^[8]

Core Principles

Intermittent fasting triggers a metabolic shift from relying on glucose as the primary energy source to utilizing stored fats, which occurs after the depletion of glycogen reserves in the liver and muscles, after approximately 24 hours of fasting, though partial shifts may begin earlier in shorter fasting periods typical of intermittent fasting. During this initial phase, the body breaks down glycogen through glycogenolysis to maintain blood glucose levels, but as these stores diminish, gluconeogenesis and lipolysis increase, leading to the production of ketone bodies from fatty acids in the liver. This adaptation promotes fat utilization for energy, enhancing metabolic flexibility.^[9] Reduced insulin levels during fasting periods improve insulin sensitivity by lowering the demand on pancreatic beta cells and facilitating greater fat oxidation. Meta-analyses of clinical trials show that intermittent fasting regimens decrease fasting insulin concentrations by an average of 13.25 μU/mL and reduce HOMA-IR scores by 0.31, indicating enhanced cellular response to insulin and reduced insulin resistance. This hormonal adjustment supports the shift toward ketone production and prevents excessive glucose storage as fat. Additionally, fasting elevates growth hormone secretion, which aids in preserving muscle mass while promoting lipolysis.^[10]^[11] Autophagy, the cellular process of self-cleaning and recycling damaged components, is initiated during prolonged fasting as nutrient deprivation signals the activation of lysosomal degradation pathways. In animal models, short-term fasting of 24 hours dramatically upregulates autophagy in neurons and other tissues, clearing dysfunctional proteins and organelles to maintain cellular homeostasis. Evidence in humans remains preliminary and suggests induction may occur after 24 hours or longer, contributing to tissue repair without caloric intake. Practical implementation of intermittent fasting requires attention to hydration and mindful refeeding to sustain benefits and prevent discomfort. Participants should consume ample water, black coffee, or unsweetened tea during fasting windows to maintain electrolyte balance and mitigate dehydration risks. When breaking a fast, opt for small portions of nutrient-dense foods such as lean proteins, vegetables, and healthy fats aligned with a Mediterranean-style diet to ease digestion and stabilize blood sugar. To avoid compensatory overeating, which can undermine metabolic gains, eat slowly and focus on balanced meals rather than high-calorie processed items.^[6]^[12]

History

Ancient and Religious Origins

The roots of intermittent fasting trace back to prehistoric human societies, where hunter-gatherer lifestyles inherently involved periods of food scarcity and abundance due to the challenges of foraging and hunting. Early humans evolved in environments characterized by intermittent access to food, leading to natural cycles of feasting and fasting that shaped metabolic adaptations.^[2] Studies of modern hunter-gatherer groups, such as the Hadza in Tanzania, reveal similar patterns of irregular eating windows influenced by seasonal availability and successful hunts, suggesting that prolonged fasting episodes were a common survival mechanism rather than a deliberate practice.^[13] In ancient civilizations, fasting emerged as a recognized therapeutic tool, particularly within Greek philosophy and early medical traditions. Hippocrates, often regarded as the father of medicine in the 5th century BCE, advocated fasting as a means to restore health by allowing the body to eliminate toxins and balance humors, prescribing abstinence from food for patients suffering from various ailments to promote recovery.^[14] This approach aligned with broader philosophical views in ancient Greece, where thinkers like Pythagoras incorporated fasting into regimens for mental clarity and physical purification, viewing it as essential for achieving harmony between body and mind.^[15] Such practices influenced subsequent medical traditions across the Mediterranean, emphasizing moderation and periodic abstinence as preventive health measures.^[16] Fasting also held profound significance in ancient religious and cultural rituals, serving as a pathway for spiritual purification and divine connection across diverse civilizations. From the earliest recorded societies in Egypt, India, and Mesopotamia, abstinence from food was integrated into ceremonies to cleanse the soul, heighten spiritual awareness, and atone for impurities, often as a communal act to foster discipline and proximity to the sacred.^[17] In these contexts, fasting transcended mere physical restraint, symbolizing renewal and alignment with cosmic or divine order, a tradition that persisted through antiquity without rigid doctrinal specifications.^[18] By the 19th and early 20th centuries, these ancient ideas resurfaced in Western alternative health movements, particularly through the natural hygiene tradition. Herbert M. Shelton, a prominent naturopath and chiropractor active in the mid-20th century, championed fasting as a core principle of natural hygiene, establishing sanitariums where supervised fasts were used to detoxify the body and treat chronic illnesses without drugs or invasive interventions.^[19] Drawing from earlier hygienists like Sylvester Graham, Shelton's approach, detailed in works such as Fasting Can Save Your Life (1964), positioned intermittent and prolonged fasting as a return to humanity's innate self-healing capacities, influencing the broader raw food and wellness movements of the era.^[20]

Modern Scientific Development

The scientific investigation of intermittent fasting (IF) began in the early 20th century with foundational animal studies demonstrating its potential health benefits. In 1909, Italian immunologist Carlo Moreschi reported that underfeeding rats slowed the growth of transplanted tumors compared to normally fed controls, marking one of the earliest links between caloric restriction— a precursor to IF— and reduced disease progression in rodents.^[21] Rodent experiments on alternate-day feeding patterns began in the late 20th century, such as a 1988 study by Siegel et al., showing improved longevity and metabolic adaptations.^[22] Initial human trials on IF emerged in the early 2000s, focusing on obesity management and building on animal data to establish IF as a feasible alternative to continuous dieting, though sample sizes were small and long-term outcomes untested.^[23] The 2000s saw influential research elevating IF's profile, particularly through neuroprotection studies. Mark Mattson, a neuroscientist at Johns Hopkins University, published seminal work in 2003 demonstrating that intermittent fasting in rodents enhanced neuronal resistance to oxidative stress and injury, independent of overall calorie reduction, via mechanisms like increased BDNF expression.^[24] His subsequent papers in the mid-2000s, including a 2005 review, linked IF to protection against neurodegenerative diseases like Alzheimer's in animal models, sparking broader interest in its brain health applications.^[25] Concurrently, Valter Longo at the University of Southern California developed the fasting-mimicking diet (FMD), a low-calorie regimen simulating fasting effects; his 2015 study in Cell Metabolism showed that periodic FMD cycles promoted multi-system regeneration, reduced IGF-1 levels, and extended healthspan in mice and humans.^[26] IF gained mainstream traction in the 2010s through popular media and publications. The 2013 book The 8-Hour Diet by David Zinczenko and Peter Moore popularized time-restricted eating by advocating an 8-hour daily feeding window, claiming metabolic resets for weight loss, which sold widely and influenced public adoption.^[27] Post-2010 coverage in outlets like The New York Times (2016) and BBC (2019) highlighted emerging evidence, contributing to IF's rise as a top diet trend by the late 2010s.^[28]^[29] Recent meta-analyses from 2024–2025 have tempered enthusiasm by comparing IF to continuous calorie restriction (CR). A 2024 Nutrients review of randomized trials found IF yielded slightly greater short-term weight loss (about 0.9 kg more) but no superior long-term metabolic improvements over CR.^[30] Similarly, a 2025 BMJ systematic review of 18 studies concluded that IF and CR produce comparable reductions in body weight (3–8%) and cardiometabolic risk factors, questioning IF's unique advantages.^[31] These findings underscore IF's viability but emphasize equivalent efficacy to established CR methods.^[32]

Types

Time-Restricted Eating

Time-restricted eating (TRE) is a form of intermittent fasting that involves limiting daily food intake to a specific window of time, typically 4 to 12 hours, followed by a fasting period of the remaining hours in a 24-hour cycle.^[33] This approach emphasizes the timing of meals rather than strict calorie restriction, making it accessible for beginners seeking a structured daily pattern.^[34] Common protocols include the 16:8 method, where individuals fast for 16 hours and eat within an 8-hour window, such as from noon to 8 p.m., allowing for two to three meals without snacks outside this period.^[35] Variations in eating window durations cater to different levels of intensity. A milder option is the 14:10 ratio, involving a 14-hour fast and 10-hour eating window, which may suit those new to fasting by providing more flexibility for meal timing.^[36] For more advanced practitioners, the 20:4 protocol, also known as the Warrior Diet, restricts eating to a 4-hour window—often in the evening—after a 20-hour fast, focusing on one large meal to mimic historical warrior feasting patterns.^[33] Effective implementation of TRE often involves aligning the eating window with circadian rhythms to optimize metabolic benefits, such as scheduling earlier windows (e.g., 8 a.m. to 4 p.m.) to match the body's natural active phase and improve glucose regulation.^[37] During the eating window, meals should prioritize nutrient-dense foods like vegetables, lean proteins, whole grains, and healthy fats to ensure balanced nutrition without overemphasizing portion control, as the focus remains on timing rather than composition alone.^[34] Adherence to TRE is facilitated by its simplicity, as it eliminates the need for calorie tracking and integrates easily into daily routines like work schedules.^[33] Additionally, flexible window placement—such as evening-focused schedules—can accommodate social eating opportunities, though challenges like weekend gatherings may occasionally disrupt consistency, with reported adherence rates of 70-85% over several days per week.^[33]

Alternate-Day and Periodic Fasting

Alternate-day fasting (ADF) involves alternating between days of unrestricted eating and days of severe calorie restriction, typically limited to 500 calories or complete abstinence from caloric intake. On fasting days, intake is often confined to low-calorie, nutrient-dense foods such as vegetables or broths to minimize hunger while providing essential micronutrients. This regimen promotes metabolic flexibility by inducing periods of energy deficit that mimic caloric restriction without daily adherence. Research indicates that ADF can be sustained for several weeks, with participants reporting moderate adherence rates comparable to continuous calorie restriction.^[38] A variant of ADF is the modified form, where fasting days allow up to 25% of daily energy needs, often around 500-600 calories, to improve tolerability. In clinical trials, this approach has demonstrated feasibility for weight management, with average weight loss of 3-8% over 3-24 weeks. The protocol emphasizes non-consecutive fasting days to allow recovery and prevent excessive fatigue.^[3] The 5:2 diet, a popular periodic restriction method, consists of five days of normal eating followed by two non-consecutive days of 500-600 calorie intake per week. Developed by Michael Mosley and popularized in the early 2010s, it aims to replicate the benefits of intermittent energy restriction while fitting into typical lifestyles. Studies show it leads to mild to moderate weight reduction, similar to other intermittent fasting protocols, with improvements in insulin sensitivity observed after 8-12 weeks. Adherence is high due to the infrequent restriction days, though individual responses vary based on baseline metabolic health.^[39]^[40] Periodic fasting entails longer fasts of 24 to 72 hours, performed once a month or quarterly, often as water-only or low-calorie regimens. This method, rooted in practices like religious observances, triggers deeper metabolic shifts such as enhanced autophagy during extended abstinence. Protocols typically recommend medical supervision for fasts exceeding 48 hours to monitor hydration and vital signs. Clinical evidence supports its use for short-term metabolic reset, with refeeding phases essential to restore glycogen stores and prevent rebound overeating.^[41]^[42] Logistics for these methods include preparation to ease entry into fasting states, such as gradually reducing carbohydrate intake 1-2 days prior to minimize withdrawal symptoms like headaches. During fasts, electrolyte supplementation—particularly sodium, potassium, and magnesium—is advised to counteract imbalances from fluid shifts and prevent symptoms like dizziness or muscle cramps. Recovery involves a phased refeeding approach: starting with light, easily digestible foods like soups or fruits over 1-2 days to avoid gastrointestinal distress and support metabolic adaptation. These strategies enhance safety and sustainability, especially for longer periodic fasts.^[43]^[44]

Calorie-Restricted Variations

Calorie-restricted variations of intermittent fasting integrate deliberate reductions in energy intake with structured fasting periods, aiming to enhance metabolic benefits while allowing nutrient-dense eating windows. These approaches differ from pure time-restricted or zero-calorie fasting by emphasizing controlled calorie deficits, often tailored for specific health or performance goals. The fasting-mimicking diet (FMD) is a prominent example, consisting of a 5-day, low-calorie, plant-based protocol designed to replicate the physiological effects of water-only fasting without complete food abstinence. On day 1, intake is approximately 1,090 kcal, reducing to 725 kcal on days 2 through 5, with a macronutrient profile low in protein (9-14%) and high in unsaturated fats (44-56%), sourced from vegetable soups, nut-based bars, and herbal teas. This regimen, developed by Valter Longo and colleagues, lowers circulating glucose, insulin, and IGF-1 levels while elevating ketone bodies, thereby promoting cellular repair and stress resistance akin to prolonged fasting. Typically cycled monthly for three months, FMD has been shown in pilot trials to reduce body weight, blood pressure, and markers of aging and diabetes risk without serious adverse effects.^[26] Intermittent energy restriction (IER) represents another hybrid method, involving periodic calorie reductions of 25-50% below maintenance needs, alternated with normal eating days over weekly or multi-week cycles. Common protocols include the 5:2 approach, with two non-consecutive days of 500-600 kcal intake followed by five ad libitum days, or alternate-day models limiting fast days to 20-25% of energy requirements. Studies indicate IER achieves comparable weight loss and metabolic improvements to continuous restriction, such as enhanced insulin sensitivity and lipid profiles, potentially due to improved adherence from the cyclical nature. These variations are often applied in clinical settings for obesity or metabolic syndrome management, with cycles spanning 8-12 weeks.^[3] Customization of calorie-restricted intermittent fasting is essential for athletes and individuals with medical conditions, focusing on macronutrient adjustments during eating periods to preserve performance and health. For athletes, protocols may incorporate higher protein intakes (1.7-2.2 g/kg body weight) within hypocaloric windows to minimize fat-free mass loss, integrated with resistance or endurance training without impairing strength, VO2max, or jump performance.^[45] In medical contexts, such as type 2 diabetes, IER requires dose adjustments for medications like insulin alongside 25-30% calorie cuts on restriction days to avoid hypoglycemia.^[1] Compliance monitoring typically involves self-reported diet journals or phone check-ins to track intake and adherence, supplemented by objective tools like continuous glucose monitors to verify fasting windows and metabolic responses.^[3]

Biological Mechanisms

Metabolic and Hormonal Changes

During intermittent fasting, the body first draws upon hepatic glycogen reserves to sustain blood glucose homeostasis. Liver glycogen stores, which provide the primary source of glucose during the initial fasting phase, are typically exhausted within 12 to 24 hours.^[9] This depletion triggers a metabolic switch to gluconeogenesis, wherein the liver synthesizes new glucose from non-carbohydrate precursors, including lactate, glycerol, and amino acids derived from muscle protein breakdown.^[9] Gluconeogenesis becomes the dominant pathway for glucose production, ensuring adequate energy supply to glucose-dependent tissues like the brain and red blood cells.^[46] Accompanying this shift are profound hormonal adaptations that orchestrate fuel mobilization. Insulin secretion declines rapidly as blood glucose falls, reducing cellular glucose uptake and storage while promoting lipolysis and proteolysis.^[47] In response, counter-regulatory hormones rise: glucagon increases to stimulate hepatic glycogenolysis and gluconeogenesis; norepinephrine elevates to enhance lipolysis through activation of hormone-sensitive lipase in adipose tissue; and growth hormone surges, further supporting fat breakdown and sparing glucose utilization.^[9] These changes collectively redirect energy metabolism from carbohydrate reliance toward fat and protein catabolism.^[46] Beyond 24 to 48 hours of fasting, once glycogen is depleted, ketogenesis intensifies in the liver, converting free fatty acids into ketone bodies such as beta-hydroxybutyrate and acetoacetate.^[9] These ketones provide an efficient alternative fuel source, particularly for the brain, which adapts to utilize up to 70% of its energy from ketones during prolonged fasting, thereby reducing dependence on glucose.^[46] To maintain energy homeostasis during extended fasting periods, the body downregulates basal metabolic rate, often by 10-20% after several days, as a adaptive mechanism to conserve limited endogenous fuel reserves.^[48] This reduction in energy expenditure helps prevent excessive tissue wasting while prioritizing essential functions.^[49]

Cellular and Genetic Processes

Intermittent fasting triggers autophagy, a conserved cellular process that degrades and recycles damaged organelles and proteins through lysosomal fusion, thereby maintaining cellular homeostasis and mitigating proteotoxic stress. This mechanism is particularly activated during nutrient deprivation, where autophagosome formation increases to engulf dysfunctional components such as mitochondria, preventing their accumulation and associated cellular damage. Studies in murine models demonstrate that short-term fasting of 24-48 hours profoundly upregulates autophagy in neuronal and hepatic tissues, with autophagosome numbers peaking around 48 hours post-restriction, highlighting its role as an adaptive response to energy scarcity. Fasting also elevates NAD+ levels, which serve as a critical cofactor for sirtuin activation, particularly SIRT1 and SIRT3, enzymes that deacetylate histones and non-histone proteins to orchestrate DNA repair and anti-aging pathways. The rise in NAD+ during fasting shifts cellular metabolism toward energy conservation, enhancing SIRT1-mediated deacetylation of targets like PGC-1α to boost mitochondrial biogenesis and antioxidant defenses, while SIRT3 targets mitochondrial proteins such as MnSOD to reduce reactive oxygen species and support genomic stability. This sirtuin-dependent reprogramming links nutrient sensing to longevity by suppressing oxidative damage and promoting repair mechanisms that counteract age-related decline.^[50] Inhibition of the mechanistic target of rapamycin (mTOR) pathway represents another key cellular response to intermittent fasting, curtailing protein synthesis and cellular growth to favor repair and survival under nutrient limitation. Reduced amino acid and insulin/IGF-1 signaling during fasting suppresses mTORC1 activity, downregulating downstream effectors like S6K to limit anabolic processes and allocate resources toward catabolic pathways, which has been shown to extend lifespan in model organisms from yeast to rodents. This transient mTOR inhibition during fasting cycles promotes cellular resilience and longevity by enabling autophagy and stress resistance without chronic suppression. Intermittent fasting further attenuates inflammation at the cellular level by dampening NF-κB signaling and proinflammatory cytokine production, fostering an anti-inflammatory milieu. Nutrient restriction inhibits NF-κB translocation and activation in immune and adipose cells, leading to decreased expression of cytokines such as IL-6 and TNF-α, as observed in rodent models of age-related inflammation. This reduction in NF-κB-driven transcription helps mitigate chronic low-grade inflammation, supporting overall cellular health and preventing inflammatory pathologies.

Research on Health Effects

Weight Management and Metabolic Health

Intermittent fasting (IF) has been associated with modest weight loss in clinical trials and meta-analyses, typically ranging from 3% to 8% of initial body weight over periods of 3 to 12 months.^[51] A 2023 randomized clinical trial in adults with type 2 diabetes found that time-restricted eating led to a 3.6% weight reduction over 6 months, outperforming continuous calorie restriction's 1.8% loss in the same population.^[51] Meta-analyses confirm that IF achieves weight reductions comparable to continuous energy restriction, with no significant superiority in overall body weight loss across diverse adult cohorts.^[52] These effects are primarily driven by underlying metabolic shifts, such as enhanced fat oxidation during fasting periods.^[53] In individuals with type 2 diabetes or prediabetes, IF interventions have demonstrated improvements in insulin resistance, as measured by the homeostatic model assessment of insulin resistance (HOMA-IR).^[54] A 2023 systematic review of trials reported significant reductions in HOMA-IR scores following 12 months of IF, alongside lowered fasting insulin levels, in patients adhering to regimens like alternate-day fasting.^[54] Similarly, a 2024 clinical trial observed decreased HOMA-IR without substantial changes in body weight, attributing the benefit to periodic fasting's impact on glucose homeostasis.^[55] These enhancements in insulin sensitivity contribute to better glycemic control, particularly in overweight or obese participants.^[56] IF also positively influences lipid profiles, with consistent evidence of reductions in triglycerides and low-density lipoprotein (LDL) cholesterol. A 2020 meta-analysis of randomized controlled trials showed that IF lowered triglycerides by approximately 0.07 mmol/L (-6.5 mg/dL) and LDL cholesterol by 0.16 mmol/L (-6.2 mg/dL) compared to non-intervention controls, across various fasting protocols.^[57] These improvements were observed in both healthy and dyslipidemic individuals, supporting IF's role in mitigating cardiometabolic risk factors associated with obesity.^[58] A 2023 review further corroborated reductions in triglycerides and LDL, noting effects comparable to energy-restricted diets without altering high-density lipoprotein levels significantly.^[59] Recent randomized controlled trials from 2024 and 2025 emphasize that sustained weight loss and metabolic benefits from IF depend heavily on long-term adherence, with effects diminishing in non-adherent participants.^[60] These studies indicate no clear superiority of IF over continuous restriction in preserving lean muscle mass during weight loss, as both approaches result in similar proportions of fat versus muscle reduction when calorie intake is equated.^[61] For instance, a 2024 trial in overweight adults found that time-restricted eating maintained muscle mass equivalently to standard dieting, but only with consistent protocol adherence over 12 weeks.^[62] Overall, while IF offers viable options for metabolic health in obesity management, its efficacy aligns closely with traditional calorie control strategies.^[31]

Disease Prevention and Longevity

Intermittent fasting (IF) has been investigated for its potential role in preventing chronic diseases through metabolic adaptations that enhance cellular resilience and reduce inflammation. Research indicates that IF may lower the risk of several age-related conditions by promoting autophagy and modulating oxidative stress, though human evidence remains preliminary and largely derived from short-term trials. These effects are thought to stem from pathways such as sirtuin activation, which supports DNA repair and metabolic efficiency.^[63] In the context of cancer prevention, animal models demonstrate that IF reduces tumor growth and incidence by limiting nutrient availability to rapidly dividing cells and enhancing immune surveillance. For instance, studies in rodents have shown that alternate-day fasting decreases mammary tumor progression and improves chemotherapy efficacy by lowering insulin-like growth factor 1 (IGF-1) levels. Human data, however, is limited to adjunctive applications; ongoing 2024-2025 oncology trials, including those funded by the National Cancer Institute, explore time-restricted eating (TRE) as a supportive therapy to mitigate treatment toxicities and potentially inhibit metastasis, with preliminary results suggesting feasibility and reduced side effects in breast and colorectal cancer patients.^[64]^[65]^[66] For cardiovascular health, IF regimens have been associated with reductions in blood pressure and markers of atherosclerosis in clinical studies lasting up to one year. A randomized trial comparing intermittent and continuous energy restriction found significant improvements in systolic blood pressure and lipid profiles after six months, alongside decreased low-density lipoprotein cholesterol oxidation, which contributes to plaque formation. These benefits are attributed to enhanced endothelial function and reduced systemic inflammation, as observed in meta-analyses of TRE interventions. However, a preliminary analysis presented at the American Heart Association's 2024 Epidemiology and Prevention conference (awaiting peer review as of November 2025) reported a 91% higher risk of cardiovascular death for eating windows of less than 8 hours compared to 12-16 hours, based on data from over 20,000 U.S. adults, highlighting potential long-term risks and the need for further validation.^[67]^[68]^[69]^[70] Neuroprotective effects of IF include increased brain-derived neurotrophic factor (BDNF) expression, which supports neuronal survival and synaptic plasticity in rodent models of Alzheimer's disease. In these models, IF elevates BDNF levels in the hippocampus, correlating with reduced amyloid-beta accumulation and improved cognitive performance, suggesting a preventive role against neurodegeneration. Human trials are emerging but focus primarily on cognitive maintenance rather than disease prevention.^[71]^[72]^[73] Regarding longevity, IF acts as a caloric restriction mimetic, extending lifespan in lower organisms like yeast and nematodes through conserved pathways such as AMP-activated protein kinase (AMPK) activation, which promotes cellular repair. In worms, periodic fasting increases mean lifespan by 20-30% by enhancing stress resistance, while yeast studies show delayed aging via similar metabolic shifts. Human equivalence remains unproven, with 2025 cohort studies indicating potential correlations between long-term IF adherence and lower all-cause mortality markers, such as reduced inflammatory biomarkers, but long-term randomized data is lacking.^[74]^[75]^[76]

Exercise and Performance Impacts

Intermittent fasting (IF) interacts with exercise by altering substrate utilization, where the body shifts toward greater reliance on fat as a fuel source during physical activity, potentially influencing endurance and strength outcomes.^[2] This metabolic adjustment, while initially challenging for high-intensity efforts, can lead to adaptive benefits over time without compromising overall athletic performance. In endurance activities, IF promotes enhanced fat oxidation during fasted training sessions, allowing athletes to sustain prolonged efforts by sparing limited glycogen stores.^[77] A 2023 systematic review of sports science literature confirmed that this increased lipid metabolism supports aerobic capacity, with no observed decline in time-to-exhaustion or maximal oxygen uptake in trained individuals practicing time-restricted eating.^[78] These adaptations are particularly evident in moderate-intensity sessions, where fasted states mimic the physiological demands of competition in endurance sports like marathon running or cycling. For strength and high-intensity performance, IF may cause initial reductions due to depleted muscle glycogen, which is critical for anaerobic efforts such as weightlifting or sprinting.^[79] Studies indicate that short-term fasting can lower peak power output in glycogen-dependent exercises by 5-10% during the first few sessions, as the body prioritizes ketone production over rapid carbohydrate breakdown.^[80] However, this effect diminishes with consistent training, as resistance exercises performed in a fasted state yield comparable gains in muscle hypertrophy and maximal strength to fed-state protocols when total caloric intake is maintained.^[81] Over 2-4 weeks, individuals engaging in IF undergo keto-adaptation, a process that boosts mitochondrial efficiency by increasing the density and oxidative capacity of these organelles in skeletal muscle.^[2] This adaptation enhances energy production from fats and ketones, reducing reliance on glucose and improving overall metabolic flexibility during exercise.^[82] Research on combined IF and endurance training shows elevated expression of genes involved in mitochondrial biogenesis, leading to sustained performance improvements without fatigue accumulation.^[83] Recent 2025 analyses of IF in athletes reveal no long-term detriment to performance metrics, including VO2 max, strength endurance, or recovery times, across various protocols like 16:8 time-restricted eating.^[84] Furthermore, IF supports post-exercise recovery by lowering systemic inflammation, as evidenced by reduced levels of markers such as interleukin-6 and C-reactive protein, which aids in minimizing muscle soreness and accelerating tissue repair.^[85] These anti-inflammatory effects are attributed to the fasting-induced autophagy and hormonal shifts, benefiting athletes in high-volume training phases.^[86]

Safety and Side Effects

Common Adverse Effects

Intermittent fasting often leads to hunger and irritability, particularly during the initial adaptation phase of the first 1-2 weeks, as the body adjusts to altered eating patterns. These symptoms arise from fluctuations in ghrelin, the primary hormone that stimulates appetite, which typically peaks early in the fasting process before stabilizing.^[87]^[88]^[89] Headaches and fatigue are also prevalent short-term effects, frequently attributed to caffeine withdrawal in habitual consumers or dehydration from reduced fluid intake during fasting windows. Low blood sugar levels may exacerbate these issues, leading to lightheadedness and low energy that generally subside as the body adapts within 7-14 days.^[90]^[91]^[92] Gastrointestinal discomfort, including constipation and acid reflux, can occur especially during extended fasting periods, due to decreased fiber consumption and potential buildup of stomach acid in the absence of food. Constipation often stems from dehydration or irregular bowel habits, while acid reflux may worsen from elevated gastric acidity without buffering meals.^[93]^[12]^[94] Recent clinical trials from 2024-2025 have reported higher dropout rates of 20-30% among participants engaging in intermittent fasting protocols, largely attributable to these common symptoms such as hunger, fatigue, and digestive issues.^[95]^[96]^[97]

Contraindications and Tolerance

Intermittent fasting is contraindicated for pregnant and breastfeeding women due to potential risks to maternal and fetal health, including nutrient deficiencies that could impair development.^[98] It is also not recommended for individuals with a history of eating disorders, as the practice may exacerbate disordered eating behaviors, such as increased binge eating or food cravings, particularly among younger females.^[99] Patients with diabetes who are on insulin therapy face heightened risks of hypoglycemia during fasting periods, necessitating careful medication adjustments and close supervision to avoid severe complications.^[100] It is also contraindicated for individuals with a history of cardiovascular disease, as fasting may increase risks of adverse cardiac events.^[4] Children and adolescents under 18 years old should avoid intermittent fasting, as their developing bodies require consistent nutrient intake for growth and metabolic stability.^[98]^[6]^[101] In the elderly, particularly frail older adults over 75, intermittent fasting may be unsuitable due to reduced metabolic flexibility, which limits the body's ability to switch efficiently between fuel sources like glucose and ketones, potentially leading to energy deficits or frailty exacerbation.^[102] Monitoring for signs of intolerance is essential, with persistent dizziness, weakness, or excessive hunger indicating potential hypoglycemia or dehydration that may require immediate cessation of the practice and medical consultation.^[100] In high-risk groups like those on insulin, frequent blood glucose checks—ideally every 2 hours initially—are advised to detect adverse effects early.^[103]

Religious and Cultural Practices

In Abrahamic Religions

In Judaism, the most prominent fasting observance is Yom Kippur, the Day of Atonement, which mandates a complete 25-hour fast from sunset to sunset, abstaining from food and drink as a means of spiritual purification and repentance.^[104] This practice, rooted in biblical commandments, emphasizes atonement for sins through self-denial and reflection, and it is observed annually by Jews worldwide, with exceptions for health reasons such as for children or the ill.^[105] The fast aligns with intermittent fasting principles by enforcing a prolonged period of caloric restriction, though its primary intent is religious rather than physiological. In Christianity, fasting traditions vary by denomination but prominently feature during Lent, a 40-day period preceding Easter that involves partial fasts, such as abstaining from meat on Fridays or limiting meals to one full meal per day, to commemorate Jesus' temptation in the wilderness and foster spiritual discipline.^[106] Eastern Orthodox Christians observe a stricter Nativity Fast during Advent, the preparatory season before Christmas, which spans about 40 days and prohibits meat and dairy products throughout, while fish is permitted on certain days such as weekends and feast days, and wine and oil are allowed on non-strict days, promoting asceticism and communal prayer.^[107]^[108] These practices, while not identical to modern intermittent fasting, incorporate time-restricted eating to enhance devotion and self-control, with adaptations in Western denominations often being less rigorous. Islam's central fasting rite occurs during Ramadan, the ninth month of the lunar calendar, where adult Muslims abstain from food, drink, smoking, and marital relations from dawn (fajr) to sunset (maghrib) for 29 or 30 days, a pillar of faith that cultivates piety, empathy for the needy, and spiritual focus.^[109] This dawn-to-sunset restriction, which can span 12 to 18 hours depending on location and season, exemplifies a structured intermittent fasting regimen observed by over a billion Muslims annually, with exemptions for the elderly, pregnant, or travelers who may compensate through charity or later fasts.^[110] Contemporary research has highlighted parallels between Ramadan fasting and intermittent fasting protocols, with some Muslim communities and health experts adapting its time-restricted window to incorporate nutritional guidance for metabolic benefits, such as improved insulin sensitivity, while preserving religious observance.^[111] Studies frame Ramadan as a natural model of intermittent fasting, prompting discussions on aligning suhoor (pre-dawn meal) and iftar (post-sunset meal) with evidence-based eating patterns to mitigate potential fatigue without compromising spiritual goals.^[112]

In Eastern Traditions

In Hinduism, Ekadashi fasting occurs twice monthly on the eleventh day of the lunar fortnight, serving as a devotional practice to honor Lord Vishnu and promote spiritual purification. This intermittent fast typically involves abstaining from grains and certain foods from sunrise to the next day's sunrise, fostering a state of mental clarity believed to align the mind with divine wisdom. Health-wise, it aligns with principles of detoxification by allowing digestive rest, akin to modern intermittent fasting, which supports metabolic balance and reduces inflammation.^[113] Buddhist monastic traditions incorporate meal timing restrictions as part of the Vinaya precepts, prohibiting the consumption of solid food after midday to cultivate mindfulness and restraint. This practice, rooted in the Dharmaguptakavinaya, limits meals to the morning hours, typically one main meal before noon, with exceptions for illness or travel, to prevent dullness that hinders meditation and to minimize distractions from lay communities. Spiritually, it enhances mental purity and supports the path to enlightenment by curbing sensory desires, while practically aiding longevity and reducing physical ailments associated with overeating. In contemporary settings, such as Chinese Buddhist nunneries, adherence varies but emphasizes health benefits like improved digestion and spiritual focus.^[114]^[115] Jainism features extreme periodic fasts during Paryushana, an annual festival of eight days for Shvetambara Jains or ten for Digambaras, dedicated to self-purification and atonement. Participants engage in varying degrees of abstinence, from partial fasts avoiding root vegetables to complete nirjala fasts without food or water, aiming to cleanse the soul of karmic impurities and foster nonviolence toward all beings.^[116] The festival culminates in Pratikraman rituals of confession and forgiveness, reinforcing ethical discipline and introspection as pathways to spiritual liberation. These practices underscore Jain emphasis on tapas (austerity) for moral and physical renewal.^[117]^[118] Cultural adaptations in Eastern traditions often integrate fasting with Ayurveda, where practices like langhana (lightening therapy) balance the doshas—vata, pitta, and kapha—through tailored intermittent abstinence. For instance, short fasts of 12-24 hours suit vata types to avoid aggravation, while kapha-dominant individuals benefit from longer liquid fasts to stimulate agni (digestive fire) and eliminate ama (toxins), promoting overall harmony between body, mind, and spirit. This holistic approach views fasting not as deprivation but as a rhythmic alignment with natural cycles for sustained vitality.^[119]

Guidelines and Recommendations

General Medical Advice

Individuals beginning intermittent fasting are advised to consult a healthcare professional prior to initiation, especially those with preexisting medical conditions, to ensure safety and appropriateness.^[1] A suitable starting approach involves the 12:12 protocol, consisting of 12 hours of eating followed by 12 hours of fasting, with gradual extensions of the fasting window over time to build tolerance.^[120]^[121] During eating periods, emphasis should be placed on consuming whole, nutrient-dense foods while achieving a balanced distribution of macronutrients—such as adequate protein, healthy fats, and complex carbohydrates—to mitigate risks of nutritional deficiencies.^[122]^[123] High-protein options like lean meats, fish, legumes, and high-fiber vegetables are particularly recommended to promote satiety and overall health.^[124] Maintaining proper hydration throughout fasting intervals is crucial, as is the intake of electrolytes including sodium and potassium, which can be sourced from salted water, broths, or supplements to support fluid balance and prevent symptoms like fatigue.^[125]^[126] The 2025 American Diabetes Association Standards of Care recognize intermittent fasting and time-restricted eating as viable eating patterns within personalized medical nutrition therapy for diabetes management, emphasizing individualized application rather than use as an isolated intervention.^[127]^[128] Practitioners should monitor for common side effects like headaches or irritability and seek medical guidance if they persist.^[12]

Regional and Organizational Guidelines

In the United States, the American Diabetes Association (ADA) recognizes intermittent fasting (IF), including time-restricted eating, as a viable eating pattern for weight management in individuals with diabetes, noting its potential to achieve 3–8% weight loss over 8–12 weeks and support glycemic control.^[127] However, the ADA emphasizes the need for medical supervision, particularly for those using insulin or sulfonylureas, due to risks of hypoglycemia and the requirement for adjusted medication dosing.^[127] In Europe, the European Association for the Study of Obesity (EASO) supports IF as part of medical nutrition therapy for overweight and obesity, including in the context of cancer, highlighting its benefits for improving insulin sensitivity, reducing inflammation, and promoting weight loss when integrated into comprehensive treatment plans.^[129] The UK's National Health Service (NHS) recommends IF approaches, such as the 5:2 method, for weight loss under professional supervision, advising a 25% calorie reduction on fasting days while prioritizing nutrient-dense foods like whole grains and lean proteins to maintain metabolic health.^[130]^[131] New Zealand's Ministry of Health endorses short-term IF for healthy adults seeking weight management, aligning it with general eating guidelines that emphasize balanced nutrition, but advises against it for individuals with diabetes on insulin or sulfonylureas due to hypoglycemia risks.^[132] In the Asia-Pacific region, guidelines from bodies like Malaysia's Ministry of Health incorporate IF into obesity management protocols, stressing personalization to avoid nutrient deficiencies.^[133] Across these regions, organizational guidelines uniformly issue stricter warnings against IF during pregnancy, citing risks of dehydration, reduced fetal growth, and complications like gestational diabetes exacerbation; for instance, the ADA and UK health authorities recommend avoiding calorie restriction to ensure at least 175 grams of daily carbohydrates for maternal and fetal health.^[134]^[135]

Societal Trends

Global Usage Patterns

Intermittent fasting (IF) has seen varying levels of adoption worldwide, with prevalence rates influenced by cultural, socioeconomic, and health awareness factors. In the United States, surveys indicate that approximately 10-13% of adults have engaged in IF practices, primarily as a weight management strategy, based on data from 2024 national health polls.^[136]^[137] Globally, adoption appears higher in urban settings of developing regions, where lifestyle diseases drive interest; for instance, a 2021 national survey in India reported that 15% of urban residents had tried IF, with rates elevated among educated youth amid rising obesity concerns.^[138] Demographically, IF is most prevalent among individuals aged 18-44, who often adopt it for metabolic health improvements and weight control, according to cross-sectional studies of users. Women constitute a larger proportion of practitioners, motivated chiefly by weight loss goals, while men frequently pursue IF to enhance athletic performance and muscle preservation, as evidenced by gender-specific analyses of fasting outcomes.^[139]^[140] Higher body mass index (BMI) correlates with greater uptake across genders, reflecting its appeal for obesity management.^[139] Regional patterns highlight stark differences: in the Middle East, IF prevalence exceeds 60% among adults in countries like Saudi Arabia, largely overlapping with non-religious extensions of Ramadan fasting traditions that promote daily time-restricted eating.^[141] In Europe, clinical case series from 2023 have shown growing interest in periodic fasting for mitigating long COVID symptoms like fatigue.^[142] However, barriers persist, particularly in food-centric societies such as those in Mediterranean or South Asian cultures, where communal meals and social dining norms create resistance, often compounded by family obligations and work schedules that disrupt fasting windows.^[143]^[144]

Commercialization and Media Influence

The commercialization of intermittent fasting (IF) has transformed it from a niche health practice into a multibillion-dollar industry, driven by the demand for weight management and wellness solutions. The global IF app market, for instance, is projected to reach USD 463 million in 2025, fueled by popular applications such as Zero and Fastic that offer timers, progress tracking, and personalized plans. Similarly, the IF software sector was valued at USD 10.5 billion in 2023 and is expected to grow to USD 18.56 billion by 2031 at a compound annual growth rate (CAGR) of 6.7%, reflecting widespread adoption through digital tools.^[145]^[146] Complementary products, including supplements and snack bars designed to support fasting windows, have also proliferated; the IF supplements market stood at USD 1.42 billion in 2024.^[147] Best-selling books like "The Obesity Code" and "The Complete Guide to Fasting" by Dr. Jason Fung have further capitalized on this trend, selling millions of copies and promoting IF protocols as accessible health strategies.^[148]^[3] Media influence has significantly amplified IF's popularity, with celebrities and social platforms playing pivotal roles in its mainstream appeal. High-profile endorsements from figures such as Jennifer Aniston, who follows the 16:8 method for sustained energy, and Chris Pratt, who credits IF for his physique transformations, have popularized the practice among audiences.^[149]^[150] Similarly, Kourtney Kardashian has shared her 16:8 routine on social media, influencing followers to adopt time-restricted eating.^[150] Social media platforms like Instagram and TikTok have accelerated this trend, with hashtags such as #intermittentfasting garnering billions of views and featuring content from influencers who demonstrate protocols alongside lifestyle tips.^[151] A 2024 survey indicated that 31% of respondents felt influenced to try dieting, including IF, through social media exposure.^[137] This media-driven surge has not been without controversy, as promotional content often emphasizes benefits while downplaying risks, leading to concerns over unregulated advice targeting vulnerable groups like adolescents. For example, TikTok ads for fasting apps have raised alarms for encouraging restrictive behaviors in teenage users.^[152] Despite these issues, the synergy between celebrity advocacy and digital marketing has solidified IF's position in popular culture, contributing to its estimated 10% adoption rate among U.S. adults by 2020.^[153]

References

[1]
Intermittent fasting: What are the benefits? - Mayo Clinic
Some evidence suggests that a 16-hour fasting, 8-hour eating cycle may raise heart disease risk compared with other time-restricted eating cycles. Intermittent ...
[2]
Flipping the Metabolic Switch: Understanding and Applying Health ...
Intermittent fasting (IF) is a term used to describe a variety of eating patterns in which no or few calories are consumed for time periods that can range ...
[3]
INTERMITTENT FASTING AND HUMAN METABOLIC HEALTH - NIH
This overview suggests that intermittent fasting regimens may be a promising approach to lose weight and improve metabolic health for people who can tolerate ...
[4]
Mayo Clinic Q and A: Is intermittent fasting a helpful practice or ...
Apr 15, 2025 · It showed that people practicing intermittent fasting are twice as likely to die from heart disease or die in general than those who don't ...Missing: definition | Show results with:definition
[5]
Effects of Intermittent Fasting on Health, Aging, and Disease
Dec 25, 2019 · Intermittent fasting stimulates autophagy and mitophagy while inhibiting the mTOR (mammalian target of rapamycin) protein-synthesis pathway.Missing: definition sources
[6]
Intermittent Fasting: What is it, and how does it work?
Intermittent fasting is an eating plan that switches between fasting and eating on a regular schedule, focusing on when you eat, not what.
[7]
Systemic Adaptions to Extreme Caloric Restrictions of Different ...
Jan 19, 2025 · Surviving long periods without food has shaped human evolution. In ancient and modern societies, prolonged fasting was/is practiced by ...Missing: context | Show results with:context
[8]
Differential Effects of One Meal per Day in the Evening on Metabolic ...
It may be reasoned from an evolutionary point of view, that the human body is physiologically habituated to less frequent meals. Metabolic flexibility (i.e., ...<|control11|><|separator|>
[9]
Physiology, Fasting - StatPearls - NCBI Bookshelf
Jul 24, 2023 · After fasting for around 24 hours, glycogen stores are depleted causing the body to utilize energy stores from adipose tissue and protein ...
[10]
Effect of Intermittent Fasting Diet on Glucose and Lipid Metabolism ...
Mar 24, 2022 · Analysis of insulin sensitivity after IF diet intervention showed that insulin levels reduced by an average of 13.25 mU/L (95% CIs: −16.69 ...
[11]
Fasting enhances growth hormone secretion and amplifies the ... - NIH
Fast-induced enhancement of GH release is achieved through combined frequency (discrete pulses) and amplitude (sinusoidal periodicities) modulation.
[12]
4 intermittent fasting side effects to watch out for - Harvard Health
There's a strong biological push to overeat following fasting periods because your appetite hormones and hunger center in your brain go into overdrive when you ...
[13]
Complex physiology and clinical implications of time-restricted eating
The early hunter-gatherers undoubtedly endured periods of fasting and feasting, because food preservation capabilities were limited and access to food depended ...Missing: prehistoric | Show results with:prehistoric
[14]
Ancient Greeks and Romans were obsessed with diet advice, too
May 16, 2025 · Those who were looking to lose weight, wrote Hippocrates, should try what we call fasting cardio: exercising on an empty stomach before eating.
[15]
Therapeutic Fasting - Nature Medicine Clinic
May 11, 2016 · Hippocrates, the father of medicine, routinely recommended prolonged fasting. Pythagoras (c582-c500), a famous Greek philosopher, would not ...
[16]
The history of fasting - Neos Kosmos
Mar 10, 2015 · Fasting has been used for health and spirituality. In ancient Egypt, ancient India and ancient Greece fasting was used for curative, preventive health purposes.
[17]
Fasting – a modern take on an ancient practice
Dec 6, 2023 · Fasting is the intentional abstinence from all or some food or drink for health or spiritual purposes, used since the dawn of civilization.Why Fast? · Types Of Fasting · Fasting GuidelinesMissing: rituals | Show results with:rituals
[18]
Fasting: A Harmonizing Spiritual and Religious Practice
1.Ancient Practices: Fasting has been an essential part of spiritual rituals in ancient cultures, used for spiritual cleansing and connecting with the divine.
[19]
Herbert M Shelton and Natural Hygiene - Health Food History
Trained in chiropractic, naturopathy, and osteopathy, he became best known as the leading voice of the “Natural Hygiene” movement, which emphasized fasting, raw ...
[20]
Why fasting is now back in fashion - The Telegraph
Apr 13, 2015 · Dr Herbert Shelton was one revered pioneer, opening “Dr Shelton's Health school” in San Antonio, Texas, in 1928. He claimed to have helped ...
[21]
Timeline of calorie restriction
Oct 2, 2024 · Research, Health (cancer), Helpful, Rodent (rat), Italian immunologist in Germany Carlo Moreschi finds that tumors transplanted into rats that ...
[22]
Alternate-day fasting and chronic disease prevention: a review of ...
Aug 5, 2025 · Most rodent studies ... Sex-Dependent Metabolic Effects in Diet-Induced Obese Rats following Intermittent Fasting Compared with Continuous Food ...<|separator|>
[23]
Massive obesity treated by intermittent fasting: A metabolic and ...
Metabolic balance and clinical studies extended over a period of nineteen months, during which time 290 days were spent fasting. Weight loss has been ...
[24]
Intermittent fasting dissociates beneficial effects of dietary restriction ...
The superior neuroprotective efficacy of IF compared with LDF feeding documented in this study is consistent with enhancement of cellular stress resistance that ...
[25]
Impact of intermittent fasting on health and disease processes
IF and PF have profound beneficial effects on many different indices of health and, importantly, can counteract disease processes and improve functional ...
[26]
A periodic diet that mimics fasting promotes multi-system ... - NIH
We developed a very low calorie/low protein fasting-mimicking diet (FMD) that causes changes in markers associated with stress resistance or longevity (IGF-1, ...
[27]
The 8-Hour Diet: Watch the Pounds Disappear Without Watching ...
30-day returnsThe 8-hour diet allows eating anything within an 8-hour window, resetting metabolism to fat-burning mode, even just three days a week.
[28]
Fasting Diets Are Gaining Acceptance - The New York Times
Mar 7, 2016 · Mattson's interest in intermittent fasting grew out of work on animals that showed that alternate-day fasting protected mice from strokes, ...
[29]
Why is intermittent fasting so popular? - BBC
Jun 3, 2019 · According to a survey by the International Food Information Council Foundation intermittent fasting (IF) was last year's most popular diet.
[30]
Is Fasting Superior to Continuous Caloric Restriction for Weight Loss ...
Oct 18, 2024 · The present systematic review and meta-analysis revealed that fasting strategies led to slightly greater short-term reductions in body weight ...
[31]
Intermittent fasting strategies and their effects on body weight and ...
Jun 18, 2025 · The current evidence provides some indication that intermittent fasting diets have similar benefits to continuous energy restriction for weight loss and ...
[32]
Evaluation of the effectiveness of intermittent fasting versus caloric ...
Mar 7, 2025 · Evaluation of the effectiveness of intermittent fasting versus caloric restriction in weight loss and improving cardiometabolic health: A ...
[33]
Time-restricted eating: Watching the clock to treat obesity
Feb 6, 2024 · TRE involves confining the eating window to 4–10 h per day and fasting for the remaining hours (14–20 h fast). During the eating window, ...
[34]
Perspective: Time-Restricted Eating—Integrating the What with the ...
Time-restricted eating (TRE) is a dietary strategy that focuses on the timing of meals, but frequently neglects the quality and quantity of food consumed.
[35]
Time-Restricted Eating: Weight Loss & Metabolic Effects in Adults
Sep 28, 2020 · This randomized clinical trial examines the effect of 16:8-hour time-restricted eating on weight loss and metabolic risk markers.
[36]
Effect of intermittent fasting 16:8 and 14:10 compared with control ...
Either IF 16:8 or 14:10 had a benefit in the percentage weight change, glucose and lipid profiles in obese diabetic patients compared with the control group.
[37]
Beneficial Effects of Early Time-Restricted Feeding on Metabolic ...
When food habits (timing and number of meals per day) are misaligned with the circadian clock, they prevent an increased risk of obesity, cardiovascular ...
[38]
Alternate-day Fasting and Chronic Disease Prevention: A Review of ...
Calorie restriction (CR) and alternate-day fasting (ADF) represent 2 different forms of dietary restriction. Although the effects of CR on chronic disease ...
[39]
A randomised controlled trial of the 5:2 diet - PMC - PubMed Central
Nov 17, 2021 · The 5:2 diet is a popular intermittent energy restriction method of weight management that awaits further evaluation.
[40]
Clinical application of intermittent fasting for weight loss - PubMed
The most studied forms of intermittent fasting include: alternate day fasting (0-500 kcal per 'fast day' alternating with ad libitum intake on 'feast days ...
[41]
Intermittent and periodic fasting, longevity and disease - PMC
Intermittent and periodic fasting (IF and PF, respectively) are emerging as safe strategies to affect longevity and healthspan by acting on cellular aging ...
[42]
Fasting: Molecular Mechanisms and Clinical Applications - PMC
Periodic fasting can reverse multiple features of the metabolic syndrome in humans: it enhances insulin sensitivity, stimulates lipolysis and reduces blood ...
[43]
Efficacy and safety of prolonged water fasting: a narrative review of ...
Jun 27, 2023 · Thus, individuals should consider taking sodium chloride supplements to prevent electrolyte loss during water fasting. ... Alternate day fasting ...
[44]
Traditional and Medical Applications of Fasting - PMC
Jan 19, 2022 · Electrolyte imbalance is likely to occur and any extreme diet (including fasting) should be carefully discussed with the general practitioner.<|control11|><|separator|>
[45]
Effects of Fasting on Metabolic Hormones and Functions
Fasting triggers a cascade of changes in the hormonal, microbiome and enzymatic environments, leading to shifted glucose and fat metabolisms.
[46]
Effects of Intermittent Fasting on the Circulating Levels and ...
Aug 27, 2021 · In humans, fasting for 37.5 hours elevates basal GH concentrations by 10-fold and reduces metabolic clearance rate of GH [92]. Other studies ...ABSTRACT · INTRODUCTION · EFFECTS OF INTERMITTENT... · CONCLUSIONS
[47]
The Effect of Fasting on Human Metabolism and Psychological Health
Jan 5, 2022 · Based on traditional, cultural, or religious backgrounds, there are types of periodic fasting applied all over the world. In ancient ...
[48]
Analysis of physiological and biochemical changes and metabolic ...
Nov 18, 2024 · The total daily energy consumption decreases by 1.9 MJ after 6 days of body weight (BW) loss fasting, but the resting energy consumption remains ...Results · Long-Term Fasting Can Reduce... · Prolonged Fasting Up To...
[49]
https://www.nature.com/articles/s41598-024-80049-2
[50]
Effect of Time-Restricted Eating on Weight Loss in Adults With Type ...
Oct 27, 2023 · In a 6-month randomized clinical trial involving 75 adults with T2D, TRE was more effective for weight loss (−3.6%) than CR (−1.8%) compared with controls.
[51]
A meta‐analysis comparing the effectiveness of alternate day fasting ...
Nov 8, 2022 · Our results ranked alternate day fasting/modified ADF as the regimen with the highest efficacy for weight loss compared with the 5:2 diet and ...
[52]
Intermittent Fasting and Obesity-Related Health Outcomes
Dec 17, 2021 · This review suggests that intermittent fasting may have a beneficial role in improving anthropometric and cardiometabolic outcomes, especially for adults with ...
[53]
Effect of Intermittent Fasting on Glycaemic Control in Patients With ...
Jan 17, 2023 · On the contrary, a study where IF was followed for 12 months reported significant reductions in fasting insulin levels and homeostatic model ...
[54]
Insulin resistance reduction, intermittent fasting, and human growth ...
Oct 3, 2024 · The trial found substantial significant reductions of both HOMA-IR and a metabolic syndrome score by intermittent fasting even after correction ...
[55]
Intermittent fasting: is there a role in the treatment of diabetes? A ...
Feb 3, 2021 · Current evidence suggests that intermittent fasting is an effective non-medicinal treatment option for type 2 diabetes.
[56]
Effects of intermittent fasting and energy-restricted diets on lipid profile
IF and ERD are effective for the improvement of circulating TC, LDL-C, and TG concentrations, but have no meaningful effects on HDL-C concentration.
[57]
Effects of intermittent fasting and energy-restricted diets on lipid profile
Conclusions. The present meta-analysis indicates that ERD and IF beneficially influence the lipid profile in humans compared with non-diet control groups.
[58]
Intermittent Fasting and Its Effects on Weight, Glycemia, Lipids, and ...
Aug 21, 2023 · This review aims to summarize the effects of various types of IF on body mass index (BMI), glycemia, lipid profile, and blood pressure
[59]
[PDF] A perspective on intermittent fasting and cardiovascular risk in the ...
Jan 17, 2025 · Intermittent fasting may improve lipid profiles and insulin sensitivity, but may not be more effective than daily caloric restriction for short ...
[60]
Optimizing muscle preservation during weight loss in patients with ...
Oct 24, 2024 · ADMF participants were advised to incorporate 1–2 days of a very-low energy diet per week as needed to maintain body weight.
[61]
Synergistic Effects of Time-Restricted Feeding and Resistance ...
Sep 11, 2024 · A common challenge in body weight management strategies, including TRF [13,14] and intermittent fasting [15], is the potential for muscle loss.2. Materials And Methods · 3. Results · 3.3. 4. Biomarkers
[62]
Intermittent fasting in the prevention and treatment of cancer - PubMed
Aug 12, 2021 · Preliminary studies suggest that prolonged fasting in some patients who have cancer is safe and potentially capable of decreasing chemotherapy-related toxicity ...
[63]
Could Intermittent Energy Restriction and Intermittent Fasting ...
Jul 15, 2016 · Animal studies and human observational data link energy restriction (ER) to reduced rates of carcinogenesis. Most of these studies have ...
[64]
Intermittent Fasting Attenuates Obesity-Induced Triple-Negative ...
Jul 1, 2024 · We investigated if obesity could hasten TNBC progression and intermittent fasting (IF) could attenuate the progression of obesity-related TNBC.Missing: oncology | Show results with:oncology
[65]
Time-restricted eating and cancer: lessons learned ... - PubMed - NIH
Jul 1, 2025 · In 2020, the National Cancer Institute funded 5 intermittent fasting studies, 4 of which focused on time-restricted eating, which addressed the ...Missing: models | Show results with:models
[66]
Effect of intermittent versus continuous energy restriction on weight ...
Mar 29, 2018 · Both intermittent and continuous energy restriction resulted in similar weight loss, maintenance and improvements in cardiovascular risk factors after one year.Missing: studies | Show results with:studies
[67]
Time-Restricted Eating to Improve Cardiovascular Health - PubMed
Mar 26, 2021 · TRE is also effective in lowering fat mass, blood pressure, triglyceride levels, and markers of oxidative stress, versus controls. This fasting ...Missing: studies | Show results with:studies
[68]
Meal Timing and Frequency: Implications for Cardiovascular ...
In this statement, we review the cardiometabolic health effects of specific eating patterns: skipping breakfast, intermittent fasting, meal frequency.Missing: atherosclerosis | Show results with:atherosclerosis
[69]
Targeting BDNF as potential strategy to optimise brain health
IF was consistently reported to upregulate BDNF and improve cognitive performance in animal models. Further research is required to assess cognitive outcomes of ...Missing: prevention rodent
[70]
Intermittent fasting and neurocognitive disorders: What the evidence ...
... BDNF and CREB. IF also reduces neuroinflammation, as shown in animal models of Alzheimer's disease, vascular cognitive impairment, and high-fat diet-induced ...Missing: rodent | Show results with:rodent
[71]
Meal size and frequency affect neuronal plasticity and vulnerability ...
DR can protect neurons against degeneration in animal models of Alzheimer's, Parkinson's and Huntington's diseases and stroke. ... The beneficial effects of DR, ...Missing: prevention | Show results with:prevention
[72]
an update on mechanism, and the role of circadian rhythm and gut ...
There is accumulating evidence that intermittent fasting (IF) is connected to improved health condition and longevity.
[73]
Fasting or caloric restriction for healthy aging - PubMed - NIH
This special will highlight the latest scientific findings related to the effects of both caloric restriction and intermittent fasting across various species ...Missing: studies | Show results with:studies
[74]
A prospective study on overweight and obese cohort - PubMed
Nov 12, 2024 · Dawn-to-dusk intermittent fasting is associated with overexpression of autophagy genes: A prospective study on overweight and obese cohort.
[75]
Fasting may change the body's hunger response - Diabetes UK
Hormones that trigger eating, like ghreli, may get amplified in response to fasting. However, ghrelin usually peaks at day 1-2 and then steadily falls. This ...
[76]
Intermittent Fasting Tips and Tricks for Beginners - EMC Healthcare
Jun 30, 2025 · Common Side Effects (Based on 2024 Research). Adaptation Phase (first 1-2 weeks):. Excessive hunger, headaches, fatigue, and mood changes ...
[77]
Does Fasting cause (or cure) Hunger? | by Dr. Jason Fung - Medium
Sep 27, 2017 · During intermittent and extended fasting, ghrelin, the main hormonal mediator of hunger does not increase to unmanageable levels. Rather it ...<|control11|><|separator|>
[78]
How Fasting Causes Headaches - Verywell Health
Nov 4, 2024 · Fasting headaches are linked to low blood sugar (hypoglycemia) and dehydration. They can also be associated with caffeine withdrawal.
[79]
9 Potential Intermittent Fasting Side Effects - Healthline
1. Hunger and cravings · 2. Headaches and lightheadedness · 3. Digestive issues · 4. Irritability and other mood changes · 5. Fatigue and low energy · 6. Bad breath.
[80]
Why do headaches and fatigue show up during intermittent fasting ...
Jul 3, 2025 · They usually stem from transient dehydration, low blood sugar, caffeine withdrawal, and electrolyte shifts, and they improve within 7–14 days ...
[81]
How might intermittent fasting cause constipation? What to know
Mar 23, 2023 · Intermittent fasting can lead to changes in eating habits and constipation. Constipation is likely due to dehydration or low fiber intake.
[82]
Intermittent Fasting And Gut Health – A Gastroenterologist's ...
For those susceptible to gastric acidity, ulcers, or reflux, prolonged fasting without food could elevate stomach acid levels, resulting in discomfort or flare ...
[83]
Is intermittent fasting right for you? | Diet and Nutrition
Sep 24, 2025 · In general, intermittent fasting is an eating pattern in which you cycle between periods of eating and periods of fasting (not eating) or ...
[84]
Intermittent fasting for weight loss in night shift workers: a three-arm ...
At 24 weeks, weight and HOMA-IR were not different between the modified IF groups compared with CER. Clinically significant improvements in weight and metabolic ...
[85]
Time-restricted eating (TRE) for obesity in general practice: study ...
Mar 8, 2025 · With a 20% dropout-rate, a total of n = 208 participants need to be recruited. Therefore, the aim was to recruit 4 to 5 participants from each ...Study Design And Setting · Data Collection Methods · Strengths And Challenges<|control11|><|separator|>
[86]
Intermittent fasting and time-restricted eating role in dietary ... - NIH
Oct 28, 2022 · Also, IF and TRE are not recommended for pregnant women or lactating women and children under 12 years old (73). Clinicians should assess and ...Missing: breastfeeding | Show results with:breastfeeding
[87]
Intermittent fasting: consider the risks of disordered eating for your ...
Oct 21, 2023 · An important risk that intermittent fasting may pose is the potential to increase risk of disordered eating, which has only recently started to be examined.<|control11|><|separator|>
[88]
Clinical Management of Intermittent Fasting in Patients with ... - NIH
Apr 18, 2019 · Medication Adjustment. Anti-diabetes medications, including sulfonylureas, meglitinides, and insulin, are associated with hypoglycemia and their ...
[89]
Fasting: How to Guide - PMC - PubMed Central
May 7, 2021 · The same attention should be pointed out for pregnant or breastfeeding women, and elderly people over 75 years old.Missing: contraindications | Show results with:contraindications
[90]
Association between CLOCK gene polymorphisms with circadian ...
Studies have shown that genetic variations in the CLOCK genes are associated with chronotype, sleep patterns, obesity, dietary energy, and nutrient consumption.
[91]
CLOCK genetic variation and metabolic syndrome risk
In 2004, Rudic et al (4) showed that mutations in the Clock gene were associated with impaired glucose tolerance, which indicates that the disruption of the ...
[92]
Fasting Safely with Diabetes - Blog - NIDDK
Aug 26, 2020 · Hyperglycemia can also become an issue because people will cut back on their diabetes medicine, especially if they're on insulin, to avoid ...
[93]
Yom Kippur | Fasting, Rules, Meaning, Holiday, Bible, & Rosh ...
Oct 15, 2025 · During Yom Kippur Jews are supposed to avoid food, drink, sexual relations, wearing leather shoes, bathing or washing (with necessary exceptions) ...
[94]
Learn about the Jewish Day of Atonement: Yom Kippur 2022 (5783 ...
Oct 2, 2022 · There is a 25-hour fast as part of Yom Kippur to cleanse the body, not as a form of punishment.
[95]
Lent | Definition, History, Meaning, Catholic, & Practices - Britannica
Oct 9, 2025 · One meal a day was allowed in the evening, and meat, fish, eggs, and butter were forbidden. The Eastern church also restricts the use of wine, ...
[96]
Festive Fasting: Inside an Orthodox Advent on a meal plan.
Jan 30, 2020 · During the Advent fast, most Orthodox Christians abstain from meat and dairy, with more specific restrictions on wine, oil and fish for certain ...
[97]
Ramadan | Islam, Fasting, Timing, Traditions, Rules, Meanings, Iftar ...
During the month of Ramadan Muslims keep a fast, abstaining from food and drink from sunrise (fajr) to sunset (maghrib), but are permitted to eat and drink ...
[98]
Ramadan | Resources | Center for Spiritual Life - Brandeis University
Muslims are required to fast on each of the 29 to 30 days of Ramadan. If unable to fast, charity or fasting days outside Ramadan may suffice.
[99]
Energy Metabolism and Intermittent Fasting: The Ramadan ...
May 27, 2019 · The Ramadan fast (RF) is a form of IF practiced by millions of adult Muslims globally for a whole lunar month every year. It entails a major ...
[100]
Effects of Ramadan intermittent fasting on performance ...
Ramadan intermittent fasting (RIF) has been shown to induce alterations in energy metabolism, hormonal fluctuations, and sleep pattern disruptions, which all ...
[101]
Intermittent Fasting on the Ekadashi Day and the Role of Spiritual ...
Jan 6, 2021 · Ekadashi, the eleventh day of the lunar fortnight is said to be conducive for the mind to be in its natural state of wisdom. Hence, if we fast ...
[102]
Buddhist precepts regarding food - Thubten Chodron
Jun 6, 2016 · The kind of asceticism that the Buddha did advocate would be, for example, we (the monastics and the anagarikas) have a precept not to eat after midday and ...Missing: restrictions | Show results with:restrictions
[103]
[PDF] The Practice of Fasting after Midday in Contemporary Chinese ...
According to monastic disciplinary texts, Buddhist monastic members are prohibited from eating solid food after midday. This rule has given rise to much debate, ...
[104]
Paryushana and the Festival of Forgiveness - The Pluralism Project
Paryushana is a Jain observance of study, reflection, and purification, lasting 8 or 10 days, concluding with confession and asking for forgiveness.
[105]
Jain Festivals of Self Purification: Paryushan & Das-Lakshan - MAHB
Aug 30, 2016 · Paryushan and Das-Lakshan are Jain festivals for spiritual purification, self-improvement, and self-introspection, aiming to control desires ...
[106]
How to Fast the Ayurvedic Way
### Ayurvedic Perspective on Fasting, Integration with Dosha Balance, Types of Fasting
[107]
A Beginner's Guide to Intermittent Fasting | The Pursuit
May 8, 2019 · A good option for beginners, then, is to fast for a set number of hours each day. This option allows you to start with fasting for around 12 hours a day.
[108]
Doctor Recommends Intermittent Fasting - Mass General Giving
Aug 20, 2020 · And third, the timing. I suggest beginning with 10 consecutive fasting hours each day. Every few weeks, add a fasting hour, until you reach 16 ...<|separator|>
[109]
Should you try intermittent fasting for weight loss? - Harvard Health
Jul 28, 2022 · More accurately, intermittent fasting refers to an eating schedule that is designed to expand the amount of time your body experiences a fasted ...Missing: definition | Show results with:definition
[110]
What is an intermittent fasting diet? - Good Food
Mar 11, 2025 · However, you should try to avoid high-calorie junk food and instead aim for well-balanced nutritious meals by incorporating lean protein, ...How To Follow An... · What Can I Eat While... · What Are The Health Benefits...
[111]
Intermittent Fasting? The Foods Dietitians Want You to Prioritize
Dec 6, 2024 · High-protein foods like chicken, fish, and tofu help keep you full, support muscle maintenance, and aid in recovery during intermittent ...
[112]
Intermittent Fasting Explained: Benefits and How To Do It Safely
Consider electrolytes. Choose electrolyte drinks, powders, tablets or water enhanced with electrolytes. Electrolytes can aid in decreasing some of the negative ...Missing: Mayo | Show results with:Mayo
[113]
Electrolytes for Fasting: Benefits and Essential Tips | Dr. Berg
Feb 24, 2020 · Sodium and potassium help maintain the body's fluid balance by controlling water movement in and out of cells and regulating urinary excretion ...
[114]
5. Facilitating Positive Health Behaviors and Well-being to Improve ...
Dec 9, 2024 · Include family or roommates in meal preparation; share the responsibilities of grocery shopping and cooking.Diabetes Self-Management... · Medical Nutrition Therapy · Physical Activity
[115]
[PDF] Nutrition Consensus Report - American Diabetes Association
Studies using personalized nutrition approaches to examine genetic, metabolomic, and microbiome variations have not yet identified specific factors that ...
[116]
European Association for the Study of Obesity (EASO) Position ...
Oct 30, 2024 · IF involves periodic cycles of fasting and eating, which can improve insulin sensitivity, reduce inflammation, and promote weight loss [9].
[117]
Intermittent fasting | My Way Diabetes | Wigan | Tameside NHS
On fasting days: · Wholegrain foods: These come under your starchy carbohydrates and will provide slow-releasing of glucose into the bloodstream. · Lean meats: A ...
[118]
Intermittent fasting | CVD - MyHealth London
By eating less on 2 days of the week and eating a healthy balanced diet on the remaining 5 days. This achieves a 25% reduction in calories.
[119]
Weight loss diets | Healthify
Jul 2, 2024 · Note: Intermittent fasting is not recommended for people with diabetes taking insulin or sulfonylureas due to the risks of hypoglycaemia.
[120]
[PDF] CLINICAL PRACTICE GUIDELINES
Intermittent fasting. There are various types of intermittent fasting. These include time restrictive diets (restricting the number of hours of eating per ...
[121]
15. Management of Diabetes in Pregnancy: Standards of Care in ...
Dec 9, 2024 · The recommended dietary reference intake for all pregnant people is a minimum of 175 g of carbohydrate (∼35% of a 2,000-calorie diet), a minimum ...Glycemic Goals in Pregnancy · Management of Diabetes in...
[122]
Fasting in pregnancy | Tommy's
We recommend that you don't fast during pregnancy for the health of you and your baby. If you decide to fast, speak to your GP or midwife to get their ...
[123]
Is Intermittent Fasting Safe and Beneficial? - Medscape
Feb 10, 2025 · A 2024 survey found that as many as 13% of Americans followed an IF regimen during the previous year. But does it really offer health benefits?
[124]
Intermittent Fasting Statistics and Trends 2024 - Vitality Pro
Sep 14, 2024 · The IFIC survey showed that about 10% of Americans aged between 18-80 use intermittent fasting as a diet.
[125]
Intermittent Fasting and Its Impact on Public Health
15% of urban Indians have tried IF, according to the 2021 National Nutrition Survey, with adoption rates greater among younger (18–35 years old), better- ...<|separator|>
[126]
Intermittent Fasting: Benefits, Side Effects, Quality of Life, and ... - NIH
Feb 7, 2023 · The IF diet is an efficient dietary plan for those aiming at a weight loss journey over a short duration, ranging from less than a month up to three months.
[127]
(PDF) Differential Impacts of Intermittent Fasting on Men and Women
Abstract · 1. Hormonal Response: Fasting can alter hormone levels in the bodies of both male and female · 2. Body Composition Changes: Male and female subjects ...
[128]
Intermittent Fasting Among Adults: Patterns, Prevalence, and Health ...
Sep 6, 2025 · The study results showed meaningful weight loss and health improvements among participants, suggesting IF may offer beneficial health outcomes.
[129]
Intermittent fasting and a no-sugar diet for Long COVID symptoms
Jul 29, 2025 · An observational study found that hospitalization and death in the acute and post-acute phases of COVID-19 were lower in people engaging in ...Missing: adoption Europe
[130]
Barriers to adherence in time-restricted eating clinical trials - Frontiers
Social events, family obligations, and work commutes are external barriers that commonly influence an individual's ability to maintain a consistent eating ...
[131]
Impact of intermittent dietary restriction on the health-related ...
May 11, 2020 · These wide-ranging food choices, gastronomies, and indigenous dietary habits coupled with different time zones and environmental and climatic ...
[132]
Exploring Intermittent Fasting App Trends 2025-2033
Rating 4.8 (1,980) Oct 26, 2025 · The global Intermittent Fasting App market is experiencing robust expansion, projected to reach an estimated USD 463 million in 2025 with a ...Missing: commercialization | Show results with:commercialization
[133]
Intermittent Fasting Software Market Size And Forecast
Rating 4.5 (44) Intermittent Fasting Software Market size was valued at USD 10.5 Billion in 2023 and is projected to reach USD 18.56 Billion by 2031, growing at a CAGR of 6.7%.Missing: commercialization | Show results with:commercialization
[134]
Intermittent Fasting Supplements Market Research Report 2033
As per our latest market intelligence, the Global Intermittent Fasting Supplements market size was valued at $1.42 billion in 2024, and is forecasted to hit ...
[135]
Intermittent Fasting Bar Market Research Report 2033
The market is expanding at a remarkable CAGR of 8.7%, and is forecasted to reach USD 4.55 billion by 2033. This significant growth is driven by rising health ...
[136]
Best Fasting and Intermittent Fasting Books (29 books) - Goodreads
1. The Obesity Code: Unlocking the Secrets of Weight Loss · Jason Fung ; 2. Eat. Stop. Eat · Brad Pilon ; 3. Fasting: an Exceptional Human Experience · Randi ...
[137]
Stars Who've Found Success With Intermittent Fasting - People.com
Jan 22, 2020 · Stars Who've Found Success with Intermittent Fasting · Jack Dorsey · Jennifer Aniston · Chris Pratt · Kourtney Kardashian · Molly Sims · Vanessa ...
[138]
9 Celebrities Who Swear By Intermittent Fasting - marie claire
Oct 16, 2020 · Kourtney Kardashian. In 2018, Kourtney Kardashian explained that she's a fan of intermittent fasting in a post made on her official app.
[139]
What adolescents see on Instagram: Content analysis of ...
Nov 14, 2023 · Abstract. Aim. To describe popular diet content visible on #intermittentfasting, #keto, and #lowcarb on adolescent social media accounts.
[140]
Why Is TikTok Advertising Dangerous Fasting Diets to Teenage Girls?
but social media is feeding them ads for apps to help girls starve themselves.
[141]
IFIC: Intermittent fasting replaces clean eating as most popular diet ...
Jun 16, 2020 · According to IFIC, about 10% of the more than 1,000 Americans 18 to 80 years of age surveyed by the group in early April follow intermittent ...Missing: commercialization | Show results with:commercialization