The hidden power of fasting

For millennia, fasting has been practiced across cultures and traditions as an act of discipline and spiritual elevation. Far more than mere deprivation, it represents a return to the essentials, an exercise in self, mastery and detachment from the material world.

Beyond its spiritual significance, modern science is now uncovering the profound effects of this ancient practice. Rather than a strain on the body, fasting emerges as a sophisticated metabolic strategy, triggering a cascade of biological processes that influence health, longevity, and brain function. From regulating circadian rhythms to activating autophagy, recent discoveries in neuroscience and cellular biology suggest that this time-honored tradition may hold unexpected keys to human well-being and adaptation.

Metabolic awakening: how fasting reignites your body’s natural defenses

A landmark study by Mark Mattson’s team at Johns Hopkins University, published in The New England Journal of Medicine, showed that fasting deeply alters human physiology. After following 200 participants for six months, the researchers observed increased insulin sensitivity, a significant drop in inflammatory markers, and a rise in ketone bodies, valuable energy molecules that protect cells from oxidative stress.
Valter Longo’s work at the University of Southern California, published in Cell Metabolism, offers further insights. His team placed 100 volunteers on three- to five-day fasts, revealing heightened immune cell regeneration and a decrease in damaged white blood cells. Fasting, therefore, may not be limited to a mere metabolic adjustment; it could literally revitalize our immune system.
In 2016, Yoshinori Ohsumi was awarded the Nobel Prize in Physiology or Medicine for his research on autophagy, an essential cellular process that becomes active during fasting. This mechanism allows cells to eliminate damaged components and recycle them for energy production. Such cellular renewal is crucial for slowing down aging and preventing certain degenerative diseases.
Additionally, recent studies, particularly those led by Valter Longo’s team, indicate that fasting could be a powerful weapon in the fight against cancer. By temporarily depriving the body of nutrients, healthy cells activate protective mechanisms, while cancer cells, with their high glucose demands, become vulnerable. This process, often described as “starving cancer cells,” holds promising potential for future oncology treatments alongside conventional therapies.
A recent study by Syeda Quratulain Gillani and her team at the University of Sialkot, published in International Journal of Biology and Biotechnology (2025), highlighted the benefits of fasting for women with polycystic ovary syndrome (PCOS). The study monitored 60 participants divided into two groups, one following a 16:8 intermittent fasting schedule and the other a 12:12 regimen, over an eight-week period. Results showed a significant reduction in body weight and body mass index (BMI), with an average loss of 6.68 kg for the 16:8 group and 7.01 kg for the 12:12 group.

Beyond weight loss, this study revealed notable improvements in metabolic parameters. There was a marked decrease in insulin resistance and lower fasting insulin levels, a key factor in managing PCOS. Moreover, participants reported more regular menstrual cycles, suggesting a potential restoration of hormonal balance. An analysis of inflammatory markers also showed a reduction in pro-inflammatory cytokines, indicating that fasting may play an important role in reducing the chronic inflammation associated with PCOS.
These findings support the idea that intermittent fasting, in addition to being an effective strategy for weight management, could be a promising approach to improving hormonal and metabolic imbalances in women with PCOS.

Rewiring the body: the science of fasting for cellular restoration

Rather than weakening the body, periodic food abstinence appears to activate remarkable biological resilience. When deprived of glucose, the body taps into its fat stores, driving the production of ketones with anti-inflammatory and neuroprotective properties. This metabolic transition is accompanied by fine-tuned regulation of hunger hormones, such as ghrelin and leptin, contributing to better appetite control.
Cardiovascular benefits are also noteworthy. A meta-analysis conducted by the National Institute on Aging, published in Circulation, revealed that intermittent fasting lowers LDL cholesterol and triglyceride levels, thereby reducing the risk of cardiovascular diseases. The underlying explanation involves insulin modulation and the reduction of chronic inflammation, key factors in preventing atherosclerosis.
Moreover, fasting’s effect on longevity is attracting growing interest. Rafael de Cabo and his team at the National Institute on Aging, in a study published in Nature, demonstrated a 30% increase in lifespan in mice subjected to periodic dietary restrictions. This longer life was accompanied by enhanced autophagy and better protection against oxidative stress, both of which are central to cellular aging.

Fasting thus appears to function as a genuine biological reset, realigning the body with natural rhythms to promote optimal cell function. Rather than a simple restriction, it is an adaptive process that compels our metabolism to tap into resources that often remain underutilized. By limiting nutrient intake for set periods, the body activates repair and protective mechanisms, thereby optimizing essential functions. This renewed connection to natural cycles opens new horizons for preventing chronic diseases, systemic inflammation, and premature aging, offering a refreshed perspective on health and well-being.

References

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.

Gillani, S. Q., et al. (2025). Exploring the impact of intermittent fasting on women with Polycystic Ovary Syndrome in Sialkot, Pakistan. International Journal of Biology and Biotechnology, 22(1), 77-83.

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

Mattson, M. P., Longo, V. D., & Harvie, M. (2017). Impact of intermittent fasting on health and disease processes. The New England Journal of Medicine, 377(2), 171-181.

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

Tooze, S., & Dikič, I. (2016). Autophagy Captures the Nobel Prize. Cell, 167, 1433-1435