A five thousand year old inscription in an Egyptian pyramid states, “Humans live on a quarter of what they eat; on the other three-quarters lives their doctor.” Although fasting has religious significance in all major religions including Hinduism, Buddhism, Christianity, Judaism and, Islam, I’m usually left flabbergasted at people’s incredulity about the incredible health benefits of long-term fasting. I, myself, am an avid follower of this venerable practice for mind-body recuperation and rejuvenation. While my usual stint lasts for a couple of days, I realized the greatest benefit from long-term fasting including a 21 days zero caloric water-only-fast that I undertook a few months prior.
The general negative connotation of the practice arise due to our misconceptions of our bodies’ ability to cope with scarcity. We have been hunters and gatherers for most of our 2.5 million years on this planet. For our prehistoric ancestors, readily available food sources were a far cry. Just like any other animals in the wild, they ate when they could get some food and fasted, although involuntarily when they did not get any food. No wonder our body had to counter this predicament by storing fat for rainy days. Usually our body is in a state of glycolysis, burning energy from blood glucose. It is only during extended fasting (lasting more than 3 days) that we enter into a state of ketosis where the stored fat is burnt instead for energy purpose. There are myriad health benefits associated with ketosis including improved cognitive function and immune system, reduced heart disease risk and even cure for cancer. How do you think our ancient ancestors were able to keep off predators and hunt for food on empty stomach? After the agricultural revolution about ten thousand years ago food became ample and readily available. However, anatomically we are still very much similar to our cave dwelling foraging ancestors.
It is a poignant irony that the modern problem facing our health is not due to lack of food but from excess of it. Moreover, eating three meals a day is more of a socio-cultural construct rather than biological need. Insinuated by food industry, there is also an ulterior business agenda associated with the concept. Intermittent fasting, where we take in calories only during a specific window of a day, usually of 6-8 hours, and restrict at other times, has become popular among the practitioners for its health benefits.