Is Time-Restricted Feeding Really Useless?
Unpacking the results of human clinical trials
With the Christian observance of Lent behind us and Ramadan, the Muslim holy month of fasting, drawing to a close, what better time to re-examine the evidence surrounding the effects of fasting in humans? Modern dietary advice often focuses on what and how much one eats but often leaves out a crucial third component of when one eats.
Time-restricted feeding (TRF) is the practice of limiting calorie intake to a specified time period. Since the average American eats over a 12-hour period, time-restricted feeding is generally defined as a form of intermittent fasting that involves limiting daily food intake to a period of 10 hours or less, followed by a daily fast of at least 14 hours.
Is Time-Restricted Eating Helpful for Weight Loss?
In September 2020, a randomized controlled trial published in JAMA Internal Medicine suggested that time-restricted eating provided neither weight loss nor metabolic benefits. Ethan Weiss, a cardiologist at UCSF and one of the study authors, even pointed to the negative results of this trial as justification to no longer participate in fasting over the Jewish holiday Yom Kippur.
