Physiology, Fasting

In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan.


Fasting is a practice that involves a restriction of food or drink intake for any period. Fasting has been practiced for a variety of reasons that range from dieting to religious beliefs to medical testing. It is commonly used in medical practice for blood glucose and lipid markers laboratory tests to aid in the diagnosis of numerous diseases as well as assessing many risk factors. Variations of fasting have been studied for their ability to improve physiological indicators related to health. Some of these factors include insulin sensitivity, blood pressure, atherogenic lipids, body fat, and inflammation. Many of these studies involve those who participate in the Islamic tradition of Ramadan since participants abstain from food and drink each day from dawn until sunset for an entire month. The compiled results show a variety of metabolic and physiological adaptations that occur from fasting. From a general perspective, this includes the changes in metabolic pathways to create energy for the body.

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