Science Update

New study demonstrates the effects of intermittent fasting on body weight and metabolic disease risk factors in obesity

Intermittent fasting has become increasingly more popular over the past few years to support weight loss, insulin resistance, and aging. However, there have been limited human clinical studies on this topic. Now, in a new study published last Friday in Nutrition and Healthy Aging, researchers demonstrated the benefits of intermittent fasting in obesity.

This was a 12-week study that included 23 patients 25 to 65 years of age. They all had a BMI ranging from 30 to 45 kg/m2, were non-diabetic, did not smoke, had no history of cardiovascular disease, had a sedentary to light active lifestyle, and were not on any weight loss, lipid- or glucose-lowering medications.

At baseline, both groups consumed their normal diet for 2 weeks. Body weight was measured weekly during this period. In addition, blood pressure and heart rate were measured at baseline and week 12 (the conclusion of the study). Lipids, fasting glucose, fasting insulin, and homocysteine were also tested.

The patients in the intermittent fasting group ate from the hours of 10:00 am to 6:00 pm and fasted from 6:00 pm to 10:00 am. During the feeding window, there were no dietary restrictions on the types or quantities of food consumed. During the fasting period, the patients were encouraged to drink plenty of water and were allowed to consume coffee, black tea, and diet soda.

The primary outcome of this study was in relation to body weight. The body weight and BMI both decreased in the intermittent fasting group compared to the control group. In addition systolic blood pressure decreased significantly in the intermittent fasting group. There were no significant changes on the other biomarkers.

Perceived hunger is a common barrier to weight loss and can be an issue with compliance on an intermittent fasting diet. Some individuals may experience fatigue, dizziness, and irritability during this transition. In these cases, exogenous ketone supplementation can be used to help decrease appetite and support weight loss. Exogenous ketone supplementation increases blood ketone levels, which may directly suppress appetite as they lower plasma ghrelin levels reduce cravings.

By Michael Jurgelewicz, DC, DACBN, DCBCN, CNS


Source: Gabel K, Hoddy K, et al. Effects of 8-hour time restricted feeding on body weight and metabolic disease risk factors in obese adults: A pilot study. Nutrition and Healthy Aging, vol. 4, no. 4, pp. 345-353, 2018.