Study Finds One Intermittent Fasting Protocol That Makes Flies Live Longer

Intermittent fasting, the blanket term that refers to different fasting protocols, has been linked to various potential health benefits, including everything from an increase in neurogenesis to weight loss and improvements in metabolic syndrome. One possible benefit is living a longer life, the topic of a new study from Columbia University Irving Medical Center.

Unlike regular fasting, which typically refers to abstaining from food for multiple days, intermittent fasting is a protocol that involves eating every day, but only within a small window of time. For some people, this means fasting for 16 hours a day and limiting eating to only an 8-hour period; for others, this can mean fasting nearly the entire day and eating only one meal.

Past studies have evaluated various intermittent fasting protocols, linking them to different possible health benefits and, in some cases, consequences, including rebound weight gain.

The new study involved fruit flies that were put on different eating protocols, including one group given unlimited access to food, another that ate during a 12-hour period during the day, another that did alternate-day 24-hour fasting, and one that involved fasting for 20 hours and then eating normally the next day (iTRF, the researchers call it).

When timed correctly, only the iTRF fasting protocol resulted in long lifespans for the flies, with the longevity benefits slightly more pronounced in female than male flies. Only the flies that fasted at night and broke the fast for lunch experienced the lifespan increase, while flies that fasted during the day and ate at night didn't get the same benefit.

Why the difference? According to the researchers, a cellular "cleaning process" called autophagy takes place after fasting, but this process only happens at night. Autophagy is the coveted effect sought by many who regularly partake in fasting as it cleans up damaged cells and slows down the aging process.

The findings show promise for potentially similar effects in humans, as well as helping pave the way for a possible drug that can induce the same benefits without the need for actual fasting and the resulting hunger that many struggle with.