Health-promoting fasting is a vital tool in the arsenal of biohacking — a practice aimed at optimizing the body’s physiological and cognitive functions. This article explores the main types of therapeutic and preventive fasting, their scientific rationale, physiological mechanisms, potential risks, and recommendations for integrating these methods into personalized biohacking strategies.

Biohacking is a systematic approach to improving health and human performance using both traditional and high-tech methods. One of its core components is controlled fasting, which activates the body’s adaptive and regenerative mechanisms. Modern research confirms that both short- and long-term fasting can enhance metabolism, autophagy, neuroplasticity, and reduce inflammation.

Scientific foundations of fasting

Key physiological effects activated during fasting include:

• Autophagy — a process of cellular recycling stimulated by nutrient deficiency (Mizushima et al., 2008).

• Ketosis — a metabolic state in which the body uses ketone bodies instead of glucose (Cahill, 2006).

• Improved Insulin Sensitivity — enhanced insulin response and stabilized blood glucose levels (Longo & Panda, 2016).

• Neurogenesis and BDNF — fasting boosts brain-derived neurotrophic factor, associated with learning and memory (Mattson et al., 2018).

Main methods of health-promoting fasting

Intermittent Fasting (IF) The most popular protocols include:

16/8 (16 hours of fasting, 8-hour eating window)

• Convenient and flexible: easily fits into most daily routines, especially by skipping breakfast.
• Weight loss support: promotes a steady calorie deficit without major restrictions.
• Blood sugar stabilization: improves insulin sensitivity.
• Autophagy stimulation: particularly in the final hours of fasting.
• Low stress on the body: suitable for most people, including beginners.

20/4 (warrior diet)

• Enhanced autophagy and ketosis: due to the extended fasting period.
• Accelerated fat burning: more time in a fat-adapted metabolic state.
• Increased growth hormone secretion: helps preserve muscle mass.
• Simplified eating pattern: just one dense meal or a short feasting window.
• Improved mental clarity: many report better focus and cognitive performance.

OMAD (one meal a day)

• Maximum autophagy activation: extended fasting deeply supports cellular repair and cleanup.
• Strong metabolic effects: significant insulin drop and robust fat mobilization.
• Time-saving and efficient: only one meal to prepare and eat per day.
• Hormonal optimization: boosts growth hormone and lowers insulin and leptin levels.
• Ideal for advanced practitioners: effective as a periodic “reset” for the body.

Studies show intermittent fasting aids weight loss, improves lipid profiles, and activates autophagy with minimal stress to the body (Patterson et al., 2015).

Periodic 24–72 hour fasting

• Deep autophagy and regeneration: extended fasting triggers cellular cleanup, apoptosis of damaged cells, and the synthesis of new ones.
• Stem cell activation: supports tissue repair and immune system rejuvenation (Longo et al., 2014).
• Improved insulin sensitivity: significant reduction in glucose and insulin levels.
• Reduction of chronic inflammation: especially beneficial for those with metabolic syndrome.
• Cognitive reset: increases BDNF levels and enhances neuroplasticity.

Extended fasting over 24–72 hours triggers deep regenerative processes, including stem cell production and immune system renewal (Longo et al., 2014). However, it requires careful preparation and supervision.

Dry fasting

• Accelerated autophagy: the absence of water intensifies stress signals, speeding up the breakdown of damaged cells.
• Metabolic shift: the body generates metabolic water from fat stores, enhancing fat-burning.
• Strong anti-inflammatory effects: short dry fasts can reduce edema and inflammation.
• Antimicrobial environment: dehydration makes the internal environment less hospitable to pathogens.
• Powerful short-term “reset”: can be effective under expert supervision when used occasionally.

This method restricts both food and water intake. It can accelerate autophagy and metabolic shift but involves high risks and should only be practiced under medical supervision.

Juice Fasting

• Gentle introduction to fasting: safe and manageable for beginners.
• Detoxification and liver support: plant-based juices are rich in antioxidants, enzymes, and phytonutrients.
• Maintains electrolyte balance: unlike dry or water-only fasting.
• Caloric restriction without hunger: allows for sustained energy levels during the fast.
• Improved skin and digestion: thanks to high vitamin and enzyme content.

This milder detoxification method supplies vitamins and enzymes while limiting calories. It’s suitable for beginners and those looking for a gentle introduction to fasting.

Integration into Biohacking Strategy

Integrating fasting methods into a biohacking routine requires a personalized approach:

Use of glucose, ketone, and HRV trackers for monitoring

• Real-time physiological monitoring: provides objective feedback on how your body responds to fasting.
• Maximizes effectiveness: helps determine optimal fasting duration and timing.
• Early detection of overload: shifts in HRV or glucose spikes can indicate excessive stress or poor adaptation.
• Personalized optimization: bio-data allows for tailoring fasting strategies to individual metabolic needs.

Combination with nutraceuticals (e.g., PQQ, NAD+, metformin to prolong autophagy effects)

• Enhanced autophagy and mitochondrial biogenesis: PQQ and NAD+ support cellular repair and energy metabolism.
• Cognitive protection: nutraceuticals help maintain brain function during calorie restriction.
• Reduced inflammation and oxidative stress: amplifies the anti-aging benefits of fasting.
• Prolonged metabolic effects: compounds like metformin act as fasting mimetics, extending the benefits beyond the fasting window.

Consideration of chronotype and circadian rhythms

• Better synchronization with hormonal cycles: fasting and eating are aligned with natural peaks of cortisol, melatonin, and other hormones.
• Improved sleep and recovery: supporting circadian rhythms enhances nighttime regeneration.
• Reduced metabolic stress: fasting during biologically unfavorable periods can disrupt homeostasis—timing it right avoids this.
• Optimized digestion and energy levels: eating earlier in the day may be more effective depending on one’s chronotype.

Gradual adaptation and cycling (e.g., 5:2 protocol or weekly caloric variation)

• Minimized side effects and stress: gradual adjustment reduces risks like hypoglycemia, fatigue, and irritability.
• Greater flexibility and sustainability: cycling prevents burnout and supports long-term adherence.
• Promotes metabolic flexibility: trains the body to efficiently switch between glucose and fat for fuel.
• Lifelong integration: easier to maintain as a lifestyle practice rather than a short-term diet.

Contraindications and Risks

• Individuals with type 1 diabetes
• Pregnant or breastfeeding women
• People with eating disorders

It is essential to balance benefits with potential stress on the body. Consultation with a physician or medically trained biohacker is strongly recommended.

Fasting methods, supported by modern scientific evidence, are becoming an integral part of biohacking. When properly integrated, they enhance not only physical health but also cognitive resilience, longevity, and metabolic function.

Fasting triggers cellular rejuvenation programs, including autophagy and mitochondrial biogenesis, while reducing inflammation and oxidative stress — key contributors to aging. Regular cycles of controlled fasting promote tissue regeneration, hormonal balance, and life extension, making it one of the most effective tools for strategic anti-aging biohacking.

References:

• Cahill, G. F. (2006). Fuel metabolism in starvation. Annual Review of Nutrition.
• Longo, V. D., & Panda, S. (2016). Fasting, circadian rhythms, and time-restricted feeding in healthy lifespan. Cell Metabolism.
• Mattson, M. P., et al. (2018). Intermittent metabolic switching, neuroplasticity and brain health. Nature Reviews Neuroscience.
• Mizushima, N., et al. (2008). Autophagy fights disease through cellular self-digestion. Nature.
• Patterson, R. E., et al. (2015). Intermittent fasting and human metabolic health. Journal of the Academy of Nutrition and Dietetics.
• Longo, V. D., et al. (2014). Fasting-mimicking diet promotes multisystem regeneration, enhanced cognitive performance, and healthspan. Cell Metabolism.