Intermittent fasting may provide significant health benefits, study shows

Reviewed by Kate Anderton, B.Sc. (Editor)Dec 10 2019

Intermittent fasting may provide significant health benefits, including improved cardiometabolic health, improved blood chemistry and reduced risk for diabetes, new research conducted in part at Texas State University indicates.

Matthew McAllister, assistant professor in the Department of Health and Human Performance, co-authored the study with Liliana Renteria, graduate research assistant in the Department of Health and Human Performance, along with Brandon Pigg and Hunter Waldman of the Department of Kinesiology at Mississippi State University. Their research, "Time-restricted feeding improves markers of Cardiometabolic health in physically active college-age men: A 4-week randomized pre-post pilot study," is published in the journal Nutrition Research (https://doi.org/10.1016/j.nutres.2019.12.001).

"What we are doing is time-restricted feeding. It is a way to use fasting each day to promote various aspects of cardiometabolic health," McAllister said.

Time-restricted feeding (TRF) has been shown to improve body composition and blood lipids, as well as reduce markers of inflammation and oxidative stress. However, those results originated from rodent models and studies with small human samples. In the Texas State study, 22 men were divided into two groups to complete a 28-day study. Subjects ate daily during one eight-hour period, for example, between 9 a.m. and 5 p.m. or between noon and 8 p.m. For 16 hours of the day, they did not eat or drink anything other than water.

While both groups underwent TRF, one group's caloric intake was controlled during meal periods to ensure they ate the same amount as before the study, while members of the other group were allowed to eat as much as they wanted.

My initial thought was that if you are going to restrict the time, you would eat fewer calories. And the reduction of daily calories would cause weight loss and other health benefits. But these benefits are found with no change in caloric intake-;things like loss in body fat, reduced blood pressure, reduced inflammation."

Matthew McAllister, assistant professor, Texas State University

Fasting blood samples were analyzed for glucose and lipids, as well as adiponectin, human growth hormone, insulin, cortisol, c-reactive protein, superoxide dismutase, total nitrate/nitrite and glutathione. Results showed that both groups experienced significant reductions in body fat, blood pressure and significant increases in adiponectin and HDL-c. No change in caloric intake was detected among members of either group.