Are you losing weight? Don't overdo it with protein!
Dieters often enrich their diet with an additional amount of protein in order to prevent a decrease in the volume of muscle tissue that often accompanies weight loss. However, when conducting a study involving 34 obese postmenopausal women, scientists from the University of Washington, working under the guidance of Professor Bettina Mittendorfer, found that the consumption of excess protein neutralizes an important beneficial effect of weight loss – normalization of insulin sensitivity, which is a critical factor for reducing the risk of diabetes.
The study involved women aged 50-65 years, whose body mass index started from 30, which corresponds to significant obesity. None of them had a diagnosis of diabetes mellitus.
The participants of the 28-week study were randomly divided into 3 groups. The women of the control group were asked to maintain their body weight at a stable level.
The women of the second group followed a weight-reducing diet containing the recommended daily protein allowance: 0.8 g per kg of body weight.
The third group followed a diet also designed for weight loss, but containing additional protein. As a result, women consumed 1.2 g of protein per kg of body weight per day.
The authors chose this approach in order to verify the validity of the widespread belief that the use of an additional amount of protein contributes to the preservation of muscle tissue during weight loss.
According to the data obtained during the study, women who consumed the recommended amount of protein had significant improvements in metabolism, including an increase in insulin sensitivity by 25-30%. This trend reduces the risk of developing diabetes mellitus and diseases of the cardiovascular system. At the same time, no such improvements were observed in women who followed a protein-rich diet, despite the fact that their body weight decreased in the same way as the body weight of women in the second group.
According to Professor Mittendorfer, it is currently unclear why, against the background of high protein content in the diet, the study participants did not improve insulin sensitivity. It is also unclear whether the revealed pattern applies to men or women with an already established diagnosis of diabetes mellitus. In the near future, the authors plan to continue studying the phenomenon they have uncovered.
Article by Gordon I. Smith et al. High-Protein Intake during Weight Loss Therapy Eliminates the Weight-Loss-Induced Improvement in Insulin Action in Obese Postmenopausal Women published in the journal Cell Reports.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of Washington University School of Medicine: High-protein diet curbs metabolic benefits of weight loss.
19.10.2016