Fasting, or abstaining from eating food for a period of time, has been practiced for millennia. Notably, it has been used for spiritual purposes and health reasons. The science behind the positive health benefits of fasting are coming to light as new research is carried out in the 21st century. Some of the benefits of fasting include:
1) Reducing oxidative damage at the cellular level
2) Reducing inflammation
2) Optimizing energy metabolism
3) Bolstering cellular protection
4) Increasing longevity
5) Strengthening the immune system
6) Disease prevention and treatment
“Fasting has the potential to delay aging and help prevent and treat diseases while minimizing the side effects caused by chronic dietary interventions.” Link
There are many types of fasting out there. Intermittent fasting is a strategy where one limits their eating window to a few hours per day (e.g. fast for 16 hours, eat during a 8 hour window). Another option is to fast one full day per week or one full day per month. Longer fasts may last two to three days or even two to three weeks and beyond. The longest fast ever recorded was done under medical supervision on water and vitamin supplements only and lasted 382 days whereby the subject went from 456 pounds to a healthy weight of 180 pounds.
One common misconception with fasting is that it is hard to do because you will be hungry all the time. In actuality, the hunger resides fully after a day or two on a complete fast. With intermittent fasting, once one becomes accustomed to it, the hunger problem goes away or at least becomes easily manageable.
Another misconception is that fasting is unhealthy because we need to eat three square meals a day. The body is very intelligent. When it doesn’t have enough food for normal metabolism, it shifts into nutritional ketosis and starts burning fat for fuel. Another smart thing the body does is selectively break down and digest “tired and worn out” cells, including immune cells. Upon re-feeding, the body will generate brand new immune cells. In this manner, fasting has a sort of rejuvenating effect on the body.
One of my favorite books written on fasting is called “The Fasting Cure” by Upton Sinclair written in 1911. The PDF can be accessed here: Link.