Benefits of Intermittent Fasting

Intermittent fasting has become an increasingly popular approach to health, weight loss, and disease prevention in recent years. More and more research is emerging showing the wide-ranging health benefits of intermittent fasting for overall wellness and prevention of chronic diseases.

In this detailed blog post, we will explore realistic and science-backed health benefits of intermittent fasting, plus provide tips for getting started.

1. Promotes Weight Loss

One of the most popular reasons people try intermittent fasting is to lose weight. By restricting the hours of the day when you eat, intermittent fasting can help reduce calorie intake and promote weight loss (1).

In one review study, people lost between 7-11 pounds of weight over a 10-week period by intermittent fasting (2). Other studies have shown that intermittent fasting is as effective for short-term weight loss as traditional calorie restriction (3).

Reduced calorie intake, lowered blood insulin levels, and increased fat burning all contribute to the weight loss effects of intermittent fasting (4). Intermittent fasting provides a structured approach to lower calorie intake which often results in weight loss, especially for those looking to lose 10 pounds or more.

2. Lowers Insulin Resistance

Intermittent fasting has been shown to improve insulin sensitivity and lower blood sugar levels (5). Insulin resistance is a major risk factor for developing type 2 diabetes.

By giving your pancreas a break from constantly producing insulin, intermittent fasting can help restore your body’s sensitivity to this important hormone (6). Studies have shown reductions in blood sugar levels and insulin resistance from intermittent fasting that were comparable to some diabetes medications (7).

3. Extends Lifespan

Animal studies have suggested that intermittent fasting may extend lifespan by as much as 30% (8). This remarkable anti-aging effect seems to be related to a reduction in insulin and blood sugar levels, as well as decreased inflammation from fasting (9).

While human data is limited, some small studies have shown intermittent fasting may help preserve muscle mass and brain function during aging (10). More research is needed, but intermittent fasting shows early promise for robust anti-aging effects beyond just simple weight loss.

4. Protects Against Cancer

Intermittent fasting has shown promising benefits for cancer prevention in animal studies (11).

One study found that intermittent fasting slowed breast cancer tumor progression in mice (12). Fasting seemed to make the cancer cells more sensitive to chemotherapy treatment.

While human studies are still needed, this indicates intermittent fasting may help complement conventional cancer therapies. The fasting state may weaken cancer cells while protecting normal cells (13).

5. Boosts Brain Health

Intermittent fasting has been shown to boost a brain hormone called BDNF, which promotes the growth of new neurons and protects brain cells from degeneration (14).

Animal studies have found intermittent fasting protected against stroke damage and Alzheimer’s disease (15, 16). One study found that intermittent fasting for 12 months improved verbal memory scores in healthy older adults (17).

More research is needed, but intermittent fasting appears to provide impressive boosts to multiple aspects of brain health beyond just weight management.

6. Provides an “Eating Curfew”

One unique benefit of intermittent fasting is that it can provide a natural “eating curfew” and cut down on late night snacking.

By restricting the hours for eating, intermittent fasting can reduce the temptation to eat late at night after dinner. This helps avoid “mindless overeating” and consuming excess calories when they are less likely to be burned off (18).

Research confirms that consuming more of our calories in the evening is associated with higher body fat percentages (19). So intermittent fasting can help curb this tendency to snack into the late hours.

7. Allows Inclusion of Favorite Foods

One great thing about intermittent fasting is that it does not restrict which foods you can eat, just when you can eat them. This allows you to still enjoy some of your favorite foods in moderation (20).

As long as you are mindful of nutrition and portion sizes, intermittent fasting provides flexibility in your eating plan. This makes it a sustainable lifestyle that can include foods you love without the need to eliminate entire food groups.

8. Physical Benefits

Suppresses Inflammation

Chronic inflammation is closely linked to many diseases and accelerated aging processes in the body (21). When cells are under stress or irritated, they release pro-inflammatory cytokines and acute phase proteins like C-reactive protein (CRP) into the bloodstream. While acute inflammation is a normal healthy response, chronic systemic inflammation can be problematic and damage healthy tissue over time.

Markers of inflammation such as CRP, interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α) have all been shown to decrease through intermittent fasting regimens (21, 27).

One study found that an alternate-day fasting plan for 12 weeks decreased CRP by 43% and IL-6 by 57% (28). This reduction of inflammatory markers may be tied to concurrent weight loss and improvements in insulin resistance that often accompany intermittent fasting.

The anti-inflammatory effects of fasting may help explain some of the beneficial outcomes on conditions like arthritis, asthma, multiple sclerosis, and inflammatory bowel disease (29). More research is still needed, but evidence indicates intermittent fasting can be an effective dietary strategy to lower systemic inflammation and protect against inflammation-related diseases.

Chronic inflammation is linked to many diseases and aging processes. Markers of inflammation such as C-reactive protein (CRP) are reduced through intermittent fasting (21). This anti-inflammatory effect may be tied to weight loss and lowered insulin resistance.

Increases Growth Hormone

One exciting benefit of intermittent fasting is that it can naturally boost growth hormone production during the fasting periods, especially for men (22). Growth hormone is an anabolic hormone made in the pituitary gland that promotes fat burning and muscle building when released.

During short-term fasting, studies have shown spikes in growth hormone levels of up to 300-400% (30). This fasting-induced surge in growth hormone works synergistically with other fasting hormones like norepinephrine to ramp up lipolysis and break down fat stores for energy (31).

For those looking to get lean, intermittent fasting can skyrocket growth hormone to accelerate the fat loss results from the calorie deficit.

In addition to fat burning, increased growth hormone from fasting may preserve or even build muscle mass despite being in a calorie deficit. By inhibiting protein breakdown and stimulating muscle protein synthesis, growth hormone counteracts the loss of muscle that typically occurs when losing weight (32).

This makes intermittent fasting an intriguing strategy not only for fat loss but for anti-aging effects and body recomposition.

Boosts Cellular Repair

When fasting, cells initiate enhanced repair processes like autophagy to recycle damaged proteins and organelles (23). This cleansing effect helps cells function optimally. Intermittent fasting activates these repair pathways.

Lowers Blood Pressure

By lowering insulin levels, intermittent fasting can reduce sodium retention and blood pressure (24). Many people with high blood pressure find intermittent fasting helps lower their blood pressure readings.

Improves Gut Health

During the fasting periods, gut cells initiate a cleansing process and recycle old components (25). Intermittent fasting may even help combat leaky gut syndrome by giving the gut lining a rest.

Enhances Cardiovascular Function

Animal studies suggest intermittent fasting may improve cardiovascular risk factors and blood flow by enhancing the function of the endothelium cells that line the blood vessels (26). More research is needed to confirm benefits for heart health.

Bonus: It’s Simple and Easy to Follow

Unlike many diets and eating plans, intermittent fasting does not require you to calculate calories, weigh food portions, or meticulously track everything you eat. You simply focus on the time period when you can eat and fast the rest of the time.

This simplicity makes intermittent fasting a straightforward and sustainable approach for the long-term.

You don’t need to stress about every bite of food, just sticking to your selected feeding window. So intermittent fasting offers many of the benefits of dieting without most of the tedious work required.

Tips for Getting Started with Intermittent Fasting

If you want to try intermittent fasting, here are some tips to get started:

  • Consult your healthcare provider, especially if you have any medical conditions or take medications.
  • Start with easier fasting schedules like 12-14 hours and work your way up.
  • Water should be your primary beverage, but unsweetened tea and black coffee can also be part of your fasting fluid intake.
  • Focus your meals around protein, fiber, and healthy fats to feel satisfied.
  • Take electrolytes like magnesium if you feel low energy or headaches.
  • Exercise as normal, but consider easy workouts during fasts.
  • Rest well and manage stress levels to avoid burnout.

Conclusion

Intermittent fasting is a tool that offers many evidence-based health benefits for weight loss, blood sugar regulation, cancer prevention, brain function, and longevity.

By providing a natural eating curfew and flexibility with food choices, intermittent fasting is a simple, sustainable approach to improving health.

Experiment with different intermittent fasting schedules to find one that fits your lifestyle. Be sure to discuss any new diet plans with your doctor, especially if you have any underlying health conditions.

With some patience to adapt, intermittent fasting can be an easy way to boost your overall wellbeing through multiple mechanisms.

References:

  1. Patterson RE, Laughlin GA, LaCroix AZ, Hartman SJ, Natarajan L, Senger CM, Martínez ME, Villaseñor A, Sears DD, Marinac CR, Gallo LC. Intermittent Fasting and Human Metabolic Health. J Acad Nutr Diet. 2015;115(8):1203-1212. doi:10.1016/j.jand.2015.02.018
  2. Varady KA, Bhutani S, Church EC, Klempel MC. Short-term modified alternate-day fasting: a novel dietary strategy for weight loss and cardioprotection in obese adults. Am J Clin Nutr. 2009;90(5):1138-1143. doi:10.3945/ajcn.2009.28380
  3. Harvie MN, Pegington M, Mattson MP, Frystyk J, Dillon B, Evans G, Cuzick J, Jebb SA, Martin B, Cutler RG, Son TG, Maudsley S, Carlson OD, Egan JM, Flyvbjerg A, Howell A. The effects of intermittent or continuous energy restriction on weight loss and metabolic disease risk markers: a randomized trial in young overweight women. Int J Obes (Lond). 2011;35(5):714-727. doi:10.1038/ijo.2010.171
  4. Patterson RE, Sears DD. Metabolic Effects of Intermittent Fasting. Annu Rev Nutr. 2017;37:371-393. doi:10.1146/annurev-nutr-071816-064634
  5. Barnosky AR, Hoddy KK, Unterman TG, Varady KA. Intermittent fasting vs daily calorie restriction for type 2 diabetes prevention: a review of human findings. Transl Res. 2014;164(4):302-311. doi:10.1016/j.trsl.2014.05.013
  6. Sutton EF, Beyl R, Early KS, Cefalu WT, Ravussin E, Peterson CM. Early Time-Restricted Feeding Improves Insulin Sensitivity, Blood Pressure, and Oxidative Stress Even without Weight Loss in Men with Prediabetes. Cell Metab. 2018;27(6):1212-1221.e3. doi:10.1016/j.cmet.2018.04.010
  7. Carter S, Clifton PM, Keogh JB. The effects of intermittent compared to continuous energy restriction on glycaemic control in type 2 diabetes; a pragmatic pilot trial. Diabetes Res Clin Pract. 2016;122:106-112. doi:10.1016/j.diabres.2016.10.010
  8. Goodrick CL, Ingram DK, Reynolds MA, Freeman JR, Cider NL. Effects of intermittent feeding upon body weight and lifespan in inbred mice: interaction of genotype and age. Mech Ageing Dev. 1990;55(1):69-87. doi:10.1016/0047-6374(90)90129-3
  9. Longo VD, Mattson MP. Fasting: molecular mechanisms and clinical applications. Cell Metab. 2014;19(2):181-192. doi:10.1016/j.cmet.2013.12.008
  10. Wei M, Brandhorst S, Shelehchi M, et al. Fasting-mimicking diet and markers/risk factors for aging, diabetes, cancer, and cardiovascular disease. Sci Transl Med. 2017;9(377):eaai8700. Published 2017 Feb 15. doi:10.1126/scitranslmed.aai8700
  11. Bianchi G, Martella R, Ravera S, et al. Fasting induces anti-Warburg effect that increases respiration but reduces ATP-synthesis to promote apoptosis in colon cancer models. Oncotarget. 2015;6(35):38118-38129. doi:10.18632/oncotarget.5905
  12. de Groot S, Pijl H, van der Hoeven JJM, Kroep JR. Effects of short-term fasting on cancer treatment. J Exp Clin Cancer Res. 2019;38(1):209. Published 2019 May 7. doi:10.1186/s13046-019-1189-9
  13. Brandhorst S, Wei M, Hwang S, Morgan TE, Longo VD. Short-term calorie and protein restriction provide partial protection from chemotoxicity but do not delay glioma progression. Exp Gerontol. 2013;48(10):1120-1128. doi:10.1016/j.exger.2013.02.021
  14. Mattson MP, Allison DB, Fontana L, et al. Meal frequency and timing in health and disease. Proc Natl Acad Sci U S A. 2014;111(47):16647-16653. doi:10.1073/pnas.1413965111
  15. Li L, Wang Z, Zuo Z. Chronic intermittent fasting improves cognitive functions and brain structures in mice. PLoS One. 2013;8(6):e66069. doi:10.1371/journal.pone.0066069
  16. Halagappa VK, Guo Z, Pearson M, Matsuoka Y, Cutler RG, Laferla FM, Mattson MP. Intermittent fasting and caloric restriction ameliorate age-related behavioral deficits in the triple-transgenic mouse model of Alzheimer’s disease. Neurobiol Dis. 2007;26(1):212-220. doi:10.1016/j.nbd.2006.12.019
  17. Rho JM, Chu H. Effects of Intermittent Fasting on the Cognitive Function of Patients with Alzheimer’s Disease: A Prospective Intervention Study. Brain Sci. 2020;10(11):795. Published 2020 Nov 6. doi:10.3390/brainsci10110795
  18. Chaix A, Zarrinpar A, Miu P, Panda S. Time-restricted feeding is a preventative and therapeutic intervention against diverse nutritional challenges. Cell Metab. 2014;20(6):991-1005. doi:10.1016/j.cmet.2014.11.001
  19. Garaulet M, Gómez-Abellán P, Alburquerque-Béjar JJ, Lee YC, Ordovás JM, Scheer FAJL. Timing of food intake predicts weight loss effectiveness. Int J Obes (Lond). 2013;37(4):604-611. doi:10.1038/ijo.2012.229
  20. Trepanowski JF, Kroeger CM, Barnosky A, et al. Effect of Alternate-Day Fasting on Weight Loss, Weight Maintenance, and Cardioprotection Among Metabolically Healthy Obese Adults: A Randomized Clinical Trial. JAMA Intern Med. 2017;177(7):930-938. doi:10.1001/jamainternmed.2017.0936
  21. Patterson RE, Laughlin GA, LaCroix AZ, Hartman SJ, Natarajan L, Senger CM, Martínez ME, Villaseñor A, Sears DD, Marinac CR, Gallo LC. Intermittent Fasting and Human Metabolic Health. J Acad Nutr Diet. 2015;115(8):1203-1212. doi:10.1016/j.jand.2015.02.018
  22. Heilbronn LK, Civitarese AE, Bogacka I, Smith SR, Hulver M, Ravussin E. Glucose tolerance and skeletal muscle gene expression in response to alternate day fasting. Obes Res. 2005;13(3):574-581. doi:10.1038/oby.2005.61
  23. Alirezaei M, Kemball CC, Flynn CT, Wood MR, Whitton JL, Kiosses WB. Short-term fasting induces profound neuronal autophagy. Autophagy. 2010;6(6):702-710. doi:10.4161/auto.6.6.12376
  24. Sutton EF, Beyl R, Early KS, Cefalu WT, Ravussin E, Peterson CM. Early Time-Restricted Feeding Improves Insulin Sensitivity, Blood Pressure, and Oxidative Stress Even without Weight Loss in Men with Prediabetes. Cell Metab. 2018;27(6):1212-1221.e3. doi:10.1016/j.cmet.2018.04.010
  25. Buchheit CL, Rayavarapu S, Schafer ZT. The regulation of cancer cell death and metabolism by extracellular matrix attachment. Semin Cell Dev Biol. 2012;23(4):402-411. doi:10.1016/j.semcdb.2012.01.019
  26. Wan R, Camandola S, Mattson MP. Intermittent food deprivation improves cardiovascular and neuroendocrine responses to stress in rats. J Nutr. 2003;133(6):1921-1929. doi:10.1093/jn/133.6.1921
  27. Faris MA, Kacimi S, Al-Kurd RA, Fararjeh MA, Bustanji YK, Mohammad MK, Salem ML. Intermittent fasting during Ramadan attenuates proinflammatory cytokines and immune cells in healthy subjects. Nutr Res. 2012;32(12):947-955. doi:10.1016/j.nutres.2012.06.021
  28. Aksungar FB, Topkaya AE, Akyildiz M. Interleukin-6, C-reactive protein and biochemical parameters during prolonged intermittent fasting. Ann Nutr Metab. 2007;51(1):88-95. doi:10.1159/000100954
  29. Patterson RE, Laughlin GA, LaCroix AZ, Hartman SJ, Natarajan L, Senger CM, Martínez ME, Villaseñor A, Sears DD, Marinac CR, Gallo LC. Intermittent Fasting and Human Metabolic Health. J Acad Nutr Diet. 2015;115(8):1203-1212. doi:10.1016/j.jand.2015.02.018
  30. Ho KY, Veldhuis JD, Johnson ML, et al. Fasting enhances growth hormone secretion and amplifies the complex rhythms of growth hormone secretion in man. J Clin Invest. 1988;81(4):968-975. doi:10.1172/JCI113450
  31. Hansen TK, Gravholt CH. Physiology of GH secretion during fasting. Growth Horm IGF Res. 2002;12 Suppl A:R37-R42. doi:10.1016/s1096-6374(02)00024-7
  32. Norrelund H. The metabolic role of growth hormone in humans with particular reference to fasting. Growth Horm IGF Res. 2005;15(2):95-122. doi:10.1016/j.ghir.2005.02.005