Considering Fasting? Here's What You Need to Know

BRMI Staff

Fasting has become one of the most talked-about health trends of the past decade. From celebrities to biohackers to your neighbor who swears by skipping breakfast, everyone seems to have an opinion about eating within specific time windows or dramatically cutting calories on certain days.

But what does the science actually say? As researchers continue to study fasting, we're getting a clearer picture of what it can do, how it works, and who might benefit. If you're considering trying intermittent fasting or another fasting approach, here's what the latest evidence reveals.

What Is Fasting?

At its core, fasting is the voluntary abstention from food (and sometimes beverages) for a specific period. This practice has existed for centuries across cultures and religions, but modern interest focuses primarily on its health applications rather than spiritual ones.

Fasting isn't starvation. It's planned, controlled, and temporary. You choose when to fast and when to eat. And unlike traditional dieting, which focuses on what you eat, fasting primarily focuses on when you eat.

The main types of fasting being studied today include:

Time-Restricted Eating (TRE): You eat all your food within a specific window each day, typically 6-12 hours, and fast for the remaining hours. The most popular version is the 16:8 method—fasting for 16 hours (including sleep) and eating within an 8-hour window.

Intermittent Energy Restriction: You drastically reduce calorie intake on certain days while eating normally on others. Common approaches include:

• The 5:2 Diet: Normal eating five days per week, 500-600 calories on two non-consecutive days

• The 4:3 Method: Normal eating four days per week, 80% calorie restriction on three non-consecutive days

• Alternate-Day Fasting: Alternating between normal eating days and very low-calorie days

Extended Fasting: Fasting for 24 hours or longer, sometimes several days. This should only be done under medical supervision due to increased risks.

Why so Many People Are Considering Fasting

Fasting appeals to people for several practical reasons:

• Simplicity: Instead of counting calories at every meal, you follow time-based rules

• Flexibility: Many approaches let you choose which days or hours to fast

• No special foods required: You don't need to buy specific products or follow complicated recipes

• Fits different lifestyles: Whether you prefer skipping breakfast or dinner, there's likely an approach that works

• Potential for multiple benefits: Beyond weight loss, research suggests metabolic and cellular health improvements

What the Latest Research Shows: The Big Picture

Here's the most important finding from recent research: fasting works primarily by helping you consume fewer calories overall. When studies control for total calorie intake—meaning participants eat the same number of calories whether fasting or not—most of the metabolic benefits disappear.

A groundbreaking study published in late 2024 made this clear. Researchers had participants eat only within an eight-hour window but maintain their normal calorie intake. Result? No improvements in insulin sensitivity, blood pressure, or cholesterol levels.

So does this mean fasting is just hype?

No. What it means is that fasting is an effective tool for achieving calorie reduction rather than a metabolic hack that works independently of energy balance. And that's actually valuable.

Fasting helps many people eat less without feeling as deprived as traditional calorie counting. It accomplishes this by:

• Reducing the number of eating opportunities each day

• Simplifying meal planning and decisions

• Improving appetite regulation and hunger hormones

• Providing clear, easy-to-follow structure

• Increasing feelings of fullness with fewer calories

Think of it this way: if fasting helps you naturally consume 300-500 fewer calories per day without constant hunger and deprivation, that's a significant practical advantage over forcing yourself to eat smaller portions at every meal.

What about meal timing?

While calorie reduction drives most benefits, meal timing does appear to matter—just not as dramatically as early claims suggested. Research shows that when you eat (particularly eating earlier in the day) can provide some additional benefits beyond just eating less. We'll explore this more below.

The Health Benefits: What Actually Works

When fasting does result in reduced calorie intake, the benefits can be substantial. Here's what recent research has found:

Weight Loss and Body Composition

Multiple 2025 studies confirm that fasting is highly effective for weight loss. A year-long trial found that the 4:3 intermittent fasting approach (restricting calories by 80% on three non-consecutive weekdays) led to more weight loss than traditional daily calorie restriction with the same weekly calorie deficit.

Why does it work? When you fast, insulin levels drop, allowing your body to access and burn stored fat more efficiently. This helps reduce both subcutaneous fat (the fat under your skin) and visceral fat (the more dangerous fat surrounding your organs that's linked to heart disease and diabetes).

Research from the University of Granada revealed something particularly interesting: the timing of your eating window matters for body composition. Eating your last meal before 5pm and fasting until 9am the next morning was especially effective for reducing abdominal fat and improving blood sugar regulation. This "early time-restricted eating" appears more beneficial than late eating windows, even when total calories are similar.

Metabolic Health and Blood Sugar Control

For people with obesity, prediabetes, or type 2 diabetes, the evidence for fasting's metabolic benefits is particularly strong.

A 2025 meta-analysis examining multiple studies found that various fasting approaches significantly reduced:

• Fasting blood sugar levels

• Insulin levels

• Insulin resistance (a precursor to type 2 diabetes)

• HbA1c (a marker of long-term blood sugar control)

Another study presented at the Endocrine Society's 2025 meeting compared three approaches in people with obesity and type 2 diabetes: intermittent energy restriction, time-restricted eating, and continuous calorie restriction. While all three helped, intermittent energy restriction showed particular advantages in reducing fasting blood glucose, improving insulin sensitivity, and lowering triglycerides. It also had the highest adherence rate at 85%.

Why does this matter?

Insulin resistance—where your cells become less responsive to insulin's signals—is central to metabolic dysfunction. It precedes type 2 diabetes and contributes to numerous other health problems. By creating periods without food intake, fasting gives your body a break from constantly producing insulin, allowing cells to become more sensitive to it again.

The changes in hunger hormones also help. Fasting affects ghrelin (the "hunger hormone") and leptin (the "fullness hormone"), helping regulate appetite more naturally and making it easier to maintain a healthy weight long-term.

Cardiovascular Health

Fasting can help reduce several key risk factors for heart disease:

Blood Lipids: Studies show reductions in LDL cholesterol ("bad" cholesterol) and triglycerides, both linked to increased heart disease risk.

Blood Pressure: Multiple studies have found modest improvements in both systolic and diastolic blood pressure.

Inflammation: Fasting appears to reduce inflammatory markers. This matters because chronic inflammation contributes to atherosclerosis (hardening of the arteries), which leads to heart attacks and strokes.

A 2025 study comparing 5:2 intermittent fasting with continuous calorie restriction in adults with overweight or obesity found improvements in cardiovascular risk scores with both approaches. The key factor? Both involved calorie reduction.

The cardiovascular benefits stem partly from weight loss itself, but also from the metabolic improvements in blood sugar regulation and insulin sensitivity that affect overall cardiovascular function.

Cellular Repair and Autophagy

One of the most fascinating aspects of fasting happens at the cellular level through a process called autophagy—literally "self-eating."

When you fast and your body shifts from using glucose to burning stored fat, it triggers autophagy. During this process, cells break down and recycle old or dysfunctional components, clearing out cellular debris and damaged proteins. Think of it as your body's recycling and renewal program.

Why does this matter for health?

Disease Prevention: Autophagy helps prevent the accumulation of damaged proteins that contribute to diseases like Alzheimer's, Parkinson's, and certain cancers.

Cellular Health: By removing dysfunctional components, autophagy keeps cells functioning optimally and may slow aspects of aging.

Recovery and Regeneration: The process supports tissue and organ health, potentially improving recovery from injuries and reducing visible signs of aging.

While most autophagy research has been conducted in animals, the cellular mechanisms appear similar in humans. Animal studies have linked enhanced autophagy through fasting to increased longevity, though we need more long-term human studies to confirm these effects in people.

Brain Health and Cognitive Function

Fasting may offer significant benefits for your brain through several mechanisms:

Increased BDNF: Fasting boosts production of brain-derived neurotrophic factor (BDNF), a protein that supports the growth and survival of brain cells. Higher BDNF levels are associated with improved memory, learning, and overall cognitive function.

Ketone Production: During fasting, your liver produces ketones as an alternative energy source when burning fat. Ketones can cross the blood-brain barrier and provide efficient fuel for your brain. Many people report improved mental clarity, focus, and cognitive performance during fasting periods, which may relate to ketone utilization.

Reduced Oxidative Stress: Fasting appears to reduce oxidative damage to brain cells. This matters because oxidative stress contributes to neurodegenerative diseases like Alzheimer's and Parkinson's disease.

Neuroprotection: Animal studies suggest fasting may help protect the brain against age-related cognitive decline, though human studies are still needed to confirm the magnitude of these protective effects.

The brain benefits appear to result from the metabolic shift that occurs during fasting, not just from weight loss, which is encouraging for the potential of fasting to support long-term brain health.

Potential Longevity Benefits

Animal studies have consistently shown that fasting can extend lifespan in various species, from yeast to mice. The mechanisms include:

• Enhanced autophagy and cellular cleanup

• Reduced inflammation throughout the body

• Improved stress resistance at the cellular level

• Better regulation of growth and metabolic hormones

• Reduced production of damaging free radicals

While we don't yet have long-term human studies proving fasting extends human lifespan, we do know it improves many markers associated with healthy aging: metabolic health, cardiovascular function, cellular repair, and brain health.

The potential for fasting to support healthier aging is one of the most exciting areas for future research.

Understanding the Timing Factor

Since we now know calorie reduction is the primary driver of benefits, when does meal timing actually matter?

Early Time-Restricted Eating shows special promise: Research consistently finds that eating earlier in the day and fasting through the evening provides advantages beyond just calorie reduction. Finishing your last meal by 4-5pm and not eating again until 8-9am appears particularly beneficial for:

• Blood sugar control

• Reducing abdominal fat

• Aligning with natural circadian rhythms

Why might this work? Your body's insulin sensitivity is naturally higher in the morning and decreases throughout the day. Eating when your body is most metabolically primed to handle food, then fasting when it's preparing for rest and repair, may optimize metabolic function.

The circadian connection: Eating irregularly or late at night disrupts your body's natural 24-hour rhythms. These disruptions are associated with increased risk of obesity, cardiovascular disease, and type 2 diabetes. Consistent eating and fasting windows help maintain healthy circadian rhythms.

However—and this is important—you still need to reduce overall calories to see the major metabolic benefits. Early time-restricted eating just seems to provide an additional edge.

Different Fasting Approaches: Finding What Works for You

Not all fasting is created equal. Different approaches work better for different people depending on their lifestyle, health goals, and personal preferences.

Time-Restricted Eating (TRE)

How it works: Eat all your food within a specific daily window, typically 6-12 hours.

Popular versions:

• 16:8 (fast 16 hours, eat within 8 hours)

• 14:10 (fast 14 hours, eat within 10 hours)

• 18:6 (fast 18 hours, eat within 6 hours)

What the evidence shows: TRE can be effective for weight loss and metabolic improvements, particularly when you choose an early eating window. The simpler structure appeals to many people—once you get used to it, it becomes automatic.

Best for: People who prefer daily consistency and don't want to dramatically restrict calories on any particular day.

Intermittent Energy Restriction

How it works: Drastically reduce calories on certain days while eating normally on others.

Popular versions:

• 5:2 Diet (500-600 calories on 2 days, normal eating on 5 days)

• 4:3 Method (80% calorie restriction on 3 days, normal eating on 4 days)

• Alternate-Day Fasting (alternating between regular eating and very low-calorie days)

What the evidence shows: Recent research suggests these approaches can be more effective than daily calorie restriction for some people. The 4:3 method showed superior weight loss in a year-long trial. For people with obesity and type 2 diabetes, intermittent energy restriction demonstrated better improvements in blood glucose and insulin sensitivity compared to other approaches.

Best for: People who prefer flexibility in when they restrict calories and who can handle more dramatic changes between "normal" and "fasting" days. The built-in flexibility appeals to those with unpredictable schedules.

Extended Fasting

How it works: Fasting for 24 hours or longer, sometimes several days.

What the evidence shows: Extended fasting appears to amplify many of the cellular processes triggered by shorter fasts, particularly autophagy. However, there's less recent research on extended fasting compared to intermittent approaches.

Important caveat: Extended fasts should only be done under medical supervision due to increased risks of electrolyte imbalances, nutrient deficiencies, and other complications.

Best for: Experienced fasters working with medical supervision, typically for specific therapeutic purposes.

Who Benefits Most from Fasting?

Research suggests fasting is particularly beneficial for:

People with overweight or obesity: Fasting provides an effective weight loss strategy, especially when combined with behavioral support and structure.

Those with type 2 diabetes or prediabetes: Multiple studies show improvements in blood sugar control, insulin sensitivity, and metabolic markers. However, anyone with diabetes should work closely with their healthcare provider, as fasting can affect medication needs and blood sugar levels.

People with metabolic syndrome: This cluster of conditions (high blood pressure, high blood sugar, excess abdominal fat, abnormal cholesterol) responds well to fasting interventions.

Individuals who prefer structure over constant monitoring: If you find it easier to follow clear time-based rules rather than tracking every calorie, fasting's structured approach may suit you better psychologically.

People seeking simplicity: Fasting eliminates constant food decisions during fasting periods, which some people find liberating.

Who Should Be Cautious or Avoid Fasting?

Fasting isn't appropriate for everyone. Consult with a healthcare provider first or avoid fasting if you:

• Have a history of eating disorders or disordered eating patterns

• Are pregnant or breastfeeding

• Are underweight or have a history of malnutrition

• Have type 1 diabetes or take medications that significantly affect blood sugar

• Are under 18 or over 65 (proceed with particular caution and medical guidance)

• Take medications that must be taken with food

• Have high physical demands (athletes in heavy training may need different approaches)

• Have certain chronic health conditions that affect metabolism or nutrition

Recent research also raises questions about individual psychological responses. A 2025 study on Ramadan fasting found changes in hedonic hunger (the drive to eat for pleasure) during fasting periods, suggesting complex psychological effects that vary from person to person.

The key point: fasting affects people differently. What works wonderfully for one person might be miserable or even harmful for another.

Practical Tips for Starting Fasting Successfully

If you decide to try fasting based on the evidence, here's how to approach it safely and sustainably:

Start Gradually

Don't jump immediately into aggressive fasting schedules. Begin with a gentle 12-hour overnight fast (like 7pm to 7am), which many people naturally do anyway. Once comfortable, gradually extend to 14 or 16 hours over several weeks. Let your body adapt.

Choose Your Window Strategically

Based on recent research, early time-restricted eating (finishing your last meal in late afternoon or early evening) appears more beneficial than eating late into the night. However, the best eating window is ultimately one you can sustain long-term.

Consider your lifestyle: Do you have family dinners? Social events? Work schedules? Your fasting plan needs to fit your actual life, not some ideal scenario.

Focus on Nutrition Quality During Eating Windows

Fasting doesn't give you a free pass to eat unlimited junk food during non-fasting periods. The quality of what you eat matters. During eating windows, prioritize:

• Lean proteins to maintain muscle mass

• Healthy fats from sources like olive oil, nuts, avocados, and fish

• Abundant vegetables and fruits for vitamins, minerals, and fiber

• Whole grains for sustained energy

• Adequate hydration throughout the day

Stay Properly Hydrated

Water, black coffee, unsweetened tea, and other zero-calorie beverages are typically allowed during fasting periods. Proper hydration is crucial, especially if you're exercising or in hot weather. Don't confuse thirst for hunger.

Consider Social Support and Behavioral Strategies

Research shows fasting interventions work better with group support, accountability, and strategies for handling challenges. This might mean:

• Joining an online community of people practicing similar fasting approaches

• Working with a registered dietitian who understands fasting protocols

• Partnering with a friend or family member

• Keeping a journal to track how you feel and identify patterns

Listen to Your Body

Pay close attention to:

• Hunger and fullness signals

• Energy levels throughout the day

• Mood and mental clarity

• Sleep quality

• Physical performance during exercise

Some initial hunger and adjustment is normal. But extreme hunger, persistent dizziness, significant weakness, brain fog beyond the first week or two, or sleep disruption are signs you may need to adjust your approach.

Build in Flexibility

One advantage highlighted in recent research is that fasting can be quite flexible. With the 4:3 approach, for instance, you can choose which days to restrict calories based on your schedule and social commitments. If you have a dinner party on a planned fasting day, switch days.

Rigid adherence can backfire. The goal is a sustainable approach you can maintain long-term, not perfect compliance for a few weeks followed by complete abandonment.

Be Patient with Adaptation

The first week or two of fasting can be challenging as your body adapts to new eating patterns. Common initial experiences include:

• Hunger during usual eating times

• Mild headaches

• Temporary energy dips

• Increased focus on food

These usually improve within 1-2 weeks as your body adjusts. If they persist or worsen, reassess whether this approach is right for you.

Common Pitfalls to Avoid

Overeating During Eating Windows

Some people compensate for fasting periods by significantly overeating when they can eat, negating any calorie deficit. Remember: total calorie intake over time still fundamentally matters for weight management.

Track your eating for a week or two to ensure you're not unconsciously consuming extra calories that cancel out your fasting efforts.

Ignoring Nutritional Needs

When you have a shorter eating window, it's even more important to ensure you're meeting your nutritional requirements. This may require planning, especially for adequate protein, essential fats, vitamins, and minerals.

If you're restricting your eating window significantly, consider working with a dietitian to ensure you're getting complete nutrition.

Pushing Through Serious Warning Signs

Some initial hunger and adjustment is normal and expected. However, extreme persistent hunger, dizziness, significant weakness, mental fog that doesn't improve after 2-3 weeks, disrupted sleep, or menstrual cycle changes in women are signs to pause and reassess.

Don't push through serious warning signs out of determination to make fasting "work." Listen to what your body is telling you.

Using Fasting as Punishment

Fasting should be a proactive health strategy, not a way to punish yourself for eating "bad" foods or to compensate for overeating at a party. This mindset can lead to unhealthy relationships with food and eating disorders.

Approach fasting as one tool for health, not as penance for eating.

Expecting Magic Without Effort

While fasting can make calorie restriction easier for many people, it's not effortless. You still need to:

• Make healthy food choices

• Get adequate sleep

• Manage stress

• Exercise regularly

• Stay hydrated

Fasting works best as part of an overall healthy lifestyle, not as a standalone solution that compensates for other unhealthy habits.

A Realistic Perspective: The Bottom Line

After reviewing the latest research from 2024 and 2025, here's what we can reasonably conclude about fasting:

Fasting can be an effective tool for:

• Weight loss and reducing body fat

• Improving blood sugar control and insulin sensitivity

• Supporting cardiovascular health

• Enhancing cellular cleanup and repair processes

• Potentially supporting brain health

• Making calorie restriction more sustainable for some people

How it works:

• Primarily by helping you consume fewer calories overall

• Possibly with some additional benefits from meal timing, especially eating earlier in the day

• By triggering beneficial cellular processes like autophagy

• By improving metabolic flexibility and hormone regulation

  
  

Important caveats:

• It's not magic—the fundamentals of energy balance still apply

• Individual responses vary significantly

• It's not suitable or necessary for everyone

• Benefits require consistency over time

• Quality of food still matters during eating windows

The most honest assessment:

Fasting is one tool in the toolbox of healthy eating strategies. For some people, it's an incredibly effective approach that aligns with their lifestyle, preferences, and metabolic needs. For others, traditional balanced eating or different dietary approaches work better.

The key is finding a sustainable approach that helps you achieve your health goals while maintaining good quality of life. Fasting might be that approach—or it might not. Either way is fine. There's no moral superiority in fasting versus other healthy eating patterns.

What We Still Need to Learn

The field of fasting research is evolving rapidly. Important questions that need more research include:

• Long-term effects: Most studies are still relatively short-term (weeks to months, occasionally a year or two). We need studies following people for 5-10+ years.

  
  

• Optimal protocols for different populations: What works best for men versus women? For different age groups? For various health conditions?

  
  

• Interaction with other factors: How does fasting interact with different types of exercise? Sleep patterns? Stress levels? Medications?

  
  

• Psychological and behavioral aspects: What determines who can sustain fasting long-term versus who abandons it?

  
  

• Individual variation: Why do some people thrive on fasting while others feel terrible? Can we predict who will respond well?

  
  

• Personalization: Could genetic, metabolic, or microbiome testing help customize fasting approaches to individuals?

As this research emerges over the next several years, our understanding of how to best use fasting for different people and purposes will continue to evolve.

Making Your Decision

If you're considering fasting:

Do your homework: Understand what you're getting into and have realistic expectations about what fasting can and cannot do.

Start conservatively: Begin with gentler approaches and shorter fasting periods. You can always progress to more aggressive protocols if desired.

Monitor objectively: Track relevant metrics like weight, energy levels, sleep quality, mood, and physical performance. Don't just rely on how you feel—sometimes we talk ourselves into or out of things.

Give it a fair trial: A week isn't enough. Plan to try it for at least 4-6 weeks to get past the initial adaptation period and see if it works for you.

Stay flexible: Be willing to adjust your approach based on what you learn about your own response. There's no prize for rigid adherence to a plan that isn't working.

Consult professionals: Especially if you have any health conditions or take medications, discuss fasting with your doctor before starting.

Be honest with yourself: If fasting makes you miserable, affects your relationships, disrupts your sleep, or triggers unhealthy thoughts about food, it's okay to stop. Not every approach works for every person.

The best diet—fasting or otherwise—is one you can sustain long-term while maintaining good physical health, mental well-being, and quality of life.

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How Fasting Might Work Against Cancer

The biological mechanisms behind fasting's potential anticancer effects are fascinating:

Differential Stress Resistance

During fasting, normal cells and cancer cells respond very differently. Healthy cells enter a protective, dormant state—essentially going into "hibernation mode" to conserve resources and protect themselves. Cancer cells, however, are already damaged and metabolically dysfunctional. They struggle to adapt to nutrient deprivation and remain vulnerable even as healthy cells protect themselves.

This creates what researchers call "differential stress resistance": normal cells become more resilient to chemotherapy and radiation while cancer cells become more vulnerable to these same treatments. It's like giving your healthy cells armor while leaving cancer cells exposed.

Metabolic Vulnerabilities

Cancer cells have altered metabolism compared to normal cells. They exhibit what's called the "Warburg effect," where they rely heavily on glucose (sugar) for energy even when oxygen is present. Normal cells can adapt to using alternative fuel sources like fat and ketones, but many cancer cells cannot.

When you fast, blood glucose drops and the body shifts to burning fat for fuel. This metabolic switch may selectively starve cancer cells of their preferred fuel while normal cells adapt just fine. It's exploiting a fundamental weakness in how cancer cells generate energy.

Reduced Growth Signals

Fasting significantly reduces levels of insulin-like growth factor-1 (IGF-1), a hormone that promotes cell growth and division. Elevated IGF-1 levels are associated with increased cancer risk and progression. By lowering IGF-1, fasting may help slow cancer cell proliferation.

Additionally, fasting enhances autophagy—the body's cellular "cleanup" process that removes damaged components and may help prevent cancerous changes in cells.

The Bottom Line

Unfortunately, the effects of intermittent fasting on human cancer incidence and prognosis remain unknown because of a lack of high-quality randomized clinical trials.

However, what is known at this time is:

• Prevention studies: Observational human studies showing associations between fasting patterns and reduced cancer risk/recurrence

• Animal treatment studies: Extensive research showing fasting alone can slow tumor growth in mice and other animals

• Human treatment studies: Virtually non-existent for fasting as a standalone treatment

The research on fasting and cancer represents one of the most scientifically intriguing applications of fasting, with plausible biological mechanisms and encouraging preliminary results. Here's a balanced summary:

What we can reasonably say:

• Fasting appears safe and feasible for many (though not all) cancer patients when properly supervised

• Fasting may enhance the effectiveness of certain cancer treatments

• It may help protect normal cells from treatment toxicity

• It improves certain metabolic markers associated with cancer progression

• Major research institutions consider it worthy of serious scientific investigation

What we cannot yet say:

• Whether fasting significantly improves cancer survival rates

• Which specific cancer types benefit most

• What the optimal fasting protocol is for different situations

• What the long-term effects are

• Whether benefits seen in studies will translate to real-world settings

What is absolutely clear:

• It should only be attempted under medical supervision

• More research is needed before it becomes standard of care

References

Studies on Time-Restricted Eating and Calorie Restriction

1. Peters, B., et al. (2024). Time-restricted eating without calorie restriction shows no metabolic benefit. Science Translational Medicine. Retrieved from: https://www.sciencedaily.com/releases/2025/12/251228020018.htm

2. Deutsches Zentrum fuer Diabetesforschung DZD. (2024). Scientists tested intermittent fasting without eating less and found no metabolic benefit. ScienceDaily. December 28, 2024.

Studies on Intermittent Fasting Protocols

3. Catenacci, V.A., et al. (2024). Randomized trial comparing 4:3 intermittent fasting to daily calorie restriction for weight loss. Annals of Internal Medicine. CU Anschutz Health and Wellness Center. Retrieved from: https://news.cuanschutz.edu/health-and-wellness/beyond-daily-calorie-counting-exploring-the-43-intermittent-fasting-approach

4. Dote-Montero, M., Clavero-Jimeno, A., Merchán-Ramírez, E., et al. (2025). Effects of early, late and self-selected time-restricted eating on visceral adipose tissue and cardiometabolic health in participants with overweight or obesity: a randomized controlled trial. Nature Medicine. doi: 10.1038/s41591-024-03375-y

5. University of Granada. (2025). Intermittent fasting is effective for weight loss and improves cardiovascular health in people with obesity problems. ScienceDaily. January 8, 2025.

Meta-Analyses and Systematic Reviews

6. Song, Q., Almutairi, A.S.H., Almutairi, M.F.A., Jamilian, P., & Abu-Zaid, A. (2025). Intermittent fasting improves metabolic outcomes in metabolic syndrome: a systematic review and meta-analysis with GRADE evaluation. Frontiers in Nutrition, 12. doi: 10.3389/fnut.2025.1664811

7. Abdollahpour, N., Seifi, N., Nosrati, M., et al. (2025). The impact of intermittent fasting on body composition and cardiometabolic outcomes in overweight and obese adults: a systematic review and meta-analysis of randomized controlled trials. Nutrition Journal, 24:120. doi: 10.1186/s12937-025-01178-6

8. Abdollahpour, N., Seifi, N., Nosrati, M., et al. (2025). Comparative effects of intermittent fasting and calorie restriction on cardiovascular health in adults with overweight or obesity. Scientific Reports. doi: 10.1038/s41598-025-32673-9

Studies on Diabetes and Metabolic Health

9. Zhang, H., et al. (2025). Intermittent energy restriction may improve outcomes in people with obesity and type 2 diabetes. Presented at ENDO 2025, the Endocrine Society's Annual Meeting, San Francisco, CA.

10. Endocrine Society. (2025). Intermittent energy restriction, time-restricted eating and continuous energy restriction can all improve blood sugar levels and body weight in people with obesity and type 2 diabetes. ENDO 2025 Press Release. July 13, 2025.

Studies on Circadian Rhythms and Meal Timing

11. Panda, S. (2018). The Circadian Code: Lose Weight, Supercharge Your Energy, and Transform Your Health from Morning to Midnight. Rodale Books.

12. Longo, V.D., & Panda, S. (2016). Fasting, circadian rhythms, and time-restricted feeding in health and disease. Cell Metabolism, 23(6), 1048-1059.

Studies on Autophagy and Cellular Health

13. Mattson, M.P., & Longo, V.D. (2016). Fasting: Molecular mechanisms and clinical applications. Cell Metabolism, 23(6), 1048-1059.

14. Lee, C., & Longo, V.D. (2016). Fasting vs. caloric restriction in cardiovascular health: mechanisms and outcomes. Current Opinion in Lipidology, 27(3), 222-228.

Studies on Brain Health

15. Mattson, M.P., Moehl, K., Ghena, N., Schmaedick, M., & Cheng, A. (2018). Intermittent metabolic switching, neuroplasticity and brain health. Nature Reviews Neuroscience, 19(2), 63-80.

Studies on Psychological Aspects of Fasting

16. Frontiers in Nutrition. (2025). The effect of intermittent fasting on hedonic hunger: a pilot prospective cohort study based on Ramadan intermittent fasting. Frontiers in Nutrition, 12. doi: 10.3389/fnut.2025.1718105

Historical and Foundational Research

17. Longo, V.D., & Fontana, L. (2010). Calorie restriction and cancer prevention: metabolic and molecular mechanisms. Trends in Pharmacological Sciences, 31(2), 89-98.

18. Cani, P.D. (2019). Human gut microbiome: hopes, threats, and promises. Gut, 68(9), 1717-1725.

General Resources on Intermittent Fasting

19. Vasim, I., Majeed, C.N., & DeBoer, M.D. (2022). Intermittent fasting and metabolic health. Nutrients, 14(3), 631. doi: 10.3390/nu14030631

20. de Cabo, R., & Mattson, M.P. (2019). Effects of intermittent fasting on health, aging, and disease. New England Journal of Medicine, 381(26), 2541-2551.

Additional Reading and Context

21. Longo, V.D. (2018). The Longevity Diet: Discover the New Science Behind Stem Cell Activation and Regeneration to Slow Aging, Fight Disease, and Optimize Weight. Penguin Random House.

22. Harvie, M., & Howell, A. (2017). Potential benefits and harms of intermittent energy restriction and intermittent fasting amongst obese, overweight and normal weight subjects—A narrative review of human and animal evidence. Behavioral Sciences, 7(1), 4.

23. Patterson, R.E., & Sears, D.D. (2017). Metabolic effects of intermittent fasting. Annual Review of Nutrition, 37, 371-393.

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