Intermittent Fasting

Intermittent fasting, also known as intermittent energy restriction, is an umbrella term for various meal timing schedules that cycle between voluntary fasting (or reduced calories intake) and non-fasting over a given period. Non-caloric, and sometimes low-caloric, drinks can be used during intermittent fasting, contrary to strict fasting which disallows fluid intake in some religious practices.

Three methods of intermittent fasting are alternate-day fasting, periodic fasting, and time-restricted feeding. Intermittent fasting may be similar to a calorie restriction diet.

The science concerning intermittent fasting is preliminary and inconclusive. The American Heart Association (AHA) states that intermittent fasting may produce weight loss, reduce insulin resistance, and lower the risk of cardiometabolic diseases, although its long-term sustainability is unknown. The US National Institute on Aging (NIA) recommends against intermittent fasting because of uncertainties about its effectiveness and safety, particularly for the elderly.

Diverse forms of intermittent fasting exist in various religious practices, including Hinduism, Islam, Orthodox Christian faith and Buddhism.