By Dr. Arun Tomson
Herbal HealthImage by TanyaJoy at Adobe Stock
Fasting for Longevity
Fasting has gained attention for its potential to improve longevity by promoting cellular repair, reducing inflammation, and optimising metabolic health. The roots of fasting as a therapeutic practice trace back to many cultures, religions, and health traditions, where it has long been used as a natural means to heal and rejuvenate the body, and as a ritual for mental and emotional clarity.
Physiological Stages of Fasting
During fasting, the body undergoes physiological changes as it shifts from using glucose as the primary energy source to relying on fat reserves and ketone bodies, a process that can bring various health benefits. Depending on metabolic changes, fasting may be categorised into the following phases:
Post-Absorptive Phase (4-8 hours)
The body fully digests food and uses glucose from recent meals as energy.
Blood glucose and insulin levels balance.
This phase primes the body for later stages of fasting, enhancing health and longevity benefits.
Glycogen Depletion Phase (8-24 hours)
The body shifts to glycogen stores in the liver and muscles for energy.
Blood sugar levels stabilise, and lower insulin levels promote fat burning.
The transition from stored glucose to fat utilisation begins.
Gluconeogenesis & Fat Burning (24-48 hours)
The liver converts amino acids and glycerol into glucose.
The body increases fat breakdown, using fatty acids for energy.
Autophagy is initiated, recycling damaged cells to reduce disease risk and support longevity.
Ketosis (48-72 hours)
The liver converts fatty acids into ketones, the primary energy source.
Ketones have neuroprotective effects, supporting brain health.
Mental clarity improves, and inflammation decreases, benefiting conditions like arthritis and autoimmune diseases.
Protein Conservation Phase (Beyond 72 hours)
The body fully shifts to fat and ketones for energy, conserving protein.
Extended fasting promotes deep cellular repair, tissue regeneration, and immune renewal.
How Does Fasting Slow the Aging Process?
Research suggests that fasting and calorie restriction can slow biological aging and support overall health.
Reduction in Oxidative Stress: Fasting lowers free radical production, reducing DNA damage.
Autophagy Activation: The body removes damaged cells, reducing inflammation and age-related diseases.
Improved Insulin Sensitivity: Stabilises blood sugar and lowers diabetes risk.
Reduced Inflammation: Decreases inflammatory markers and enhances metabolic health.
Hormone Regulation: Supports growth hormone production, aiding tissue repair and muscle maintenance.
Telomere Protection: May slow the shortening of telomeres, potentially extending cellular lifespan.
Types of Fasting
Intermittent Fasting
Alternating periods of fasting and eating. Common methods include:
16/8 Method: Fasting for 16 hours, eating within an 8-hour window.
5:2 Diet: Eating normally for five days, restricting calorie intake on two non-consecutive days.
Extended Fasting
Fasting beyond 24 hours, such as 48 or 72-hour fasts, often with water or clear non-caloric liquids. Should be done under guidance.
Therapeutic Fasting
A structured approach used for specific health conditions, performed under expert supervision. According to naturopathic principles:"Fasting doesn’t cure disease but creates the environment to heal."
This includes periods of limited foods (e.g., liquids, fruits) to restore balance, promote detoxification, and enhance overall health. Therapeutic fasting is increasingly recognised for its potential benefits in holistic health practices.
While fasting isn’t a single solution for aging, its effects on cellular repair, metabolic health, and inflammation show promising benefits for longevity and healthy aging.
About the Author
Arun K. Tomson is a naturopathic physician and director of AyurMa at Four Seasons Resort Maldives at Landaa Giraavaru, where he leads an expert team in Ayurveda, yoga, and wellness. He helps individuals discover their body’s ability to heal through diet, exercise, and natural treatments.