The Costs and Benefits of Intermittent Fasting

Intermittent fasting has quickly become one of the hottest diet trends in the fitness community, and with studies demonstrating positive effects resulting from the diet, it is a no-brainer why. However, a lot of trendy diets catch fire because of widespread media attention and inflated promises that are only focused on the benefits, while paying little or no attention to some of the unwanted side effects. Also, anyone interested in adopting a new diet should be aware that studies typically have really specific instructions for participants, and adopting a similar diet is perfectly fine if it is under the supervision of one’s doctor or registered dietitian.

In a recent study (“Effects of Eight Weeks of Time-Restricted Feeding [16/8] on Basal Metabolism, Maximal Strength, Body Composition, Inflammation, and Cardiovascular Risk Factors in Resistance-Trained Males”. T. Moro, G. Tinsley, G. Marcolin, Q. Pacelli, G. Battaglia, A. Palma, P. Gentil, M. Neri, A. Paoli. Journal of Translational Medicine, 2016), researchers sought to look into some of the physiological and hormonal changes that may occur when comparing intermittent fasting with a normal diet.

The researchers found that the intermittent fasting diet produced a greater decrease in fat mass and reduced inflammation, which confirms similar results from other studies about intermittent fasting. Also, in the study, the test subjects (34 resistance trained males with at least five years of continuous exercise experience) partook in a total body exercise regimen, working out three days a week. Researchers discovered similar measurements of muscle mass between intermittent fasting and the normal diet.

Interestingly, participants on the intermittent fasting diet had reduced levels of testosterone and insulin like growth factor 1 (IGF-1). This demonstrates that individuals looking to train for increased muscle size may not achieve their desired results with an intermittent fasting diet. Since the result showed that muscle mass was maintained and body fat was reduced, it may work for someone looking for better muscle definition.

The thought of decreased levels of testosterone may create discomfort for most men, but more studies would be needed to determine if the reduced testosterone is merely a temporary event. Nevertheless, it would behoove the individual to take precaution by seeking guidance from a registered dietitian prior to adopting this diet or any other new dietary trend.