Intermittent fasting 101: What are the benefits of 16-hour intermittent fasting?

Intermittent fasting (IF) has gained significant attention in the health and wellness community for its potential to improve various aspects of human health. While recent discussions have raised concerns about IF and heart health, it’s important to approach this topic with a balanced perspective, recognizing the need for ongoing research while also acknowledging the substantial evidence supporting the benefits of IF. This article aims to provide a comprehensive overview of the positive impacts of intermittent fasting, supported by reputable publications and research studies.

Does intermittent fasting help you lose weight?

One of the most well-documented benefits of intermittent fasting is its impact on metabolic health. Studies have shown that IF can lead to improvements in weight management, insulin sensitivity, and cardiovascular risk factors.

  • Weight management and obesity: A 2024 umbrella review of 23 meta-analyses found that IF significantly reduced waist circumference and fat mass, while also improving important biochemical markers such as fasting insulin, low-density lipoprotein cholesterol, total cholesterol, and triacylglycerols in adults with overweight or obesity (1).  Several studies have reported weight loss, a reduction in fat mass, and improved body composition as a result of intermittent fasting (2-4).
  • Insulin sensitivity: Research published in Cell Metabolism in 2018 demonstrated that IF enhances insulin sensitivity, even independent of weight loss (5). In another study, IF improved the body’s post-meal glucose metabolism to a greater extent than caloric restriction alone (6). Improved insulin sensitivity is crucial for the prevention of type 2 diabetes and supports overall metabolic health.
  • Cardiovascular health: IF can lead to reductions in blood pressure, cholesterol levels, and inflammatory markers, which are all beneficial for heart health (7).

Does intermittent fasting affect mental health?

Beyond metabolic benefits, intermittent fasting has been associated with improvements in brain health and mental well-being.

  • Neuroprotection: A review article in The New England Journal of Medicine (2019) collated research that suggests that IF may enhance brain health and stave off neurodegenerative diseases through mechanisms like increased stress resistance and reduced inflammation (8).
  • Mood improvement: A study in The Journal of Nutrition, Health and Aging (2013) found that IF can improve mood, possibly through changes in brain chemistry and hormonal balance (9).

Intermittent fasting and longevity

Emerging evidence points to the potential of IF in promoting longevity and improving cellular health, primarily through mechanisms like autophagy, where cells remove and recycle damaged components.

  • Autophagy and longevity: A study in Nature Communications (2024) demonstrated that a fasting-mimicking diet triggers biological changes that correspond to a reduced biological age (10). In addition, IF was demonstrated to promote autophagy in liver, fat, brain, and muscle, which is associated with increased lifespan and reduction in age-related and chronic metabolic diseases (11).

Conclusion

While it’s crucial to consider all aspects of research on intermittent fasting, including potential concerns, the wealth of evidence supporting its benefits for metabolic health, cognitive function, and overall well-being is undeniable. As with any health intervention, individual responses can vary, and it’s important for individuals to consult with healthcare professionals before starting any new dietary regimen or intermittent fasting schedule. Ongoing research will continue to shed light on the complex interactions between intermittent fasting, health, and disease, ensuring that recommendations are based on the most current scientific evidence.

References

The studies and reviews referenced in this article are included below. These publications provide a strong foundation for the benefits associated with intermittent fasting and underscore the importance of evidence-based practice in health and wellness.

 

  1. Sun, Ming-Li et al. (2024). Intermittent fasting and health outcomes: An umbrella review of systematic reviews and meta-analyses of randomised controlled trials. eClinicalMedicine, Volume 70, 102519
  2. Wilkinson, M. J., Manoogian, E. N. C., Zadourian, A., Lo, H., Fakhouri, S., Shoghi, A., Wang, X., Fleischer, J. G., Navlakha, S., Panda, S., & Taub, P. R. (2020). Ten-Hour Time-Restricted Eating Reduces Weight, Blood Pressure, and Atherogenic Lipids in Patients with Metabolic Syndrome. Cell metabolism, 31(1), 92–104.e5. https://doi.org/10.1016/j.cmet.2019.11.004
  3. Varady, K.A., Bhutani, S., Klempel, M.C. et al. Alternate day fasting for weight loss in normal weight and overweight subjects: a randomized controlled trial. Nutr J 12, 146 (2013). https://doi.org/10.1186/1475-2891-12-146
  4. Moro, T., Tinsley, G., Bianco, A. et al. Effects of eight weeks of time-restricted feeding (16/8) on basal metabolism, maximal strength, body composition, inflammation, and cardiovascular risk factors in resistance-trained males. J Transl Med 14, 290 (2016). https://doi.org/10.1186/s12967-016-1044-0
  5. Sutton, E. F., Beyl, R., Early, K. S., Cefalu, W. T., Ravussin, E., & Peterson, C. M. (2018). Early Time-Restricted Feeding Improves Insulin Sensitivity, Blood Pressure, and Oxidative Stress Even without Weight Loss in Men with Prediabetes. Cell metabolism, 27(6), 1212–1221.e3. https://doi.org/10.1016/j.cmet.2018.04.010
  6. Teong, X.T., Liu, K., Vincent, A.D. et al. Intermittent fasting plus early time-restricted eating versus calorie restriction and standard care in adults at risk of type 2 diabetes: a randomized controlled trial. Nat Med 29, 963–972 (2023). https://doi.org/10.1038/s41591-023-02287-7
  7. Malinowski, B., Zalewska, K., Węsierska, A., Sokołowska, M. M., Socha, M., Liczner, G., Pawlak-Osińska, K., & Wiciński, M. (2019). Intermittent Fasting in Cardiovascular Disorders-An Overview. Nutrients, 11(3), 673. https://doi.org/10.3390/nu11030673
  8. de Cabo, R., & Mattson, M. P. (2019). Effects of Intermittent Fasting on Health, Aging, and Disease. The New England journal of medicine, 381(26), 2541–2551. https://doi.org/10.1056/NEJMra1905136
  9. Hussin, N. M., Shahar, S., Teng, N. I., Ngah, W. Z., & Das, S. K. (2013). Efficacy of fasting and calorie restriction (FCR) on mood and depression among ageing men. The journal of nutrition, health & aging, 17(8), 674–680. https://doi.org/10.1007/s12603-013-0344-9
  10. Brandhorst, S., Levine, M.E., Wei, M. et al. Fasting-mimicking diet causes hepatic and blood markers changes indicating reduced biological age and disease risk. Nat Commun 15, 1309 (2024). https://doi.org/10.1038/s41467-024-45260-9
  11. Martinez-Lopez, N., Tarabra, E., Toledo, M., Garcia-Macia, M., Sahu, S., Coletto, L., Batista-Gonzalez, A., Barzilai, N., Pessin, J. E., Schwartz, G. J., Kersten, S., & Singh, R. (2017). System-wide Benefits of Intermeal Fasting by Autophagy. Cell metabolism, 26(6), 856–871.e5. https://doi.org/10.1016/j.cmet.2017.09.020