HEALTH NEWS

Study Title:

Whey Protein Offsets Metabolic Damage from a High Fat Diet

Study Abstract

Consuming a high-fat (HF) diet produces excessive weight gain, adiposity, and metabolic complications associated with risk for developing type 2 diabetes and fatty liver disease. This study evaluated the influence of whey protein isolate (WPI) on systemic energy balance and metabolic changes in mice fed a HF diet. Female C57BL/6J mice received for 11 wk a HF diet, with or without 100 g WPI/L drinking water. Energy consumption and glucose and lipid metabolism were examined. WPI mice had lower rates of body weight gain and percent body fat and greater lean body mass, although energy consumption was unchanged. These results were consistent with WPI mice having higher basal metabolic rates, respiratory quotients, and hepatic mitochondrial respiration. Health implications for WPI were reflected in early biomarkers for fatty liver disease and type 2 diabetes. Livers from WPI mice had significantly fewer hepatic lipid droplet numbers and less deposition of nonpolar lipids. Furthermore, WPI improved glucose tolerance and insulin sensitivity. We conclude that in mice receiving a HF diet, consumption of WPI results in higher basal metabolic rates and altered metabolism of dietary lipids. Because WPI mice had less hepatosteatosis and insulin resistance, WPI dietary supplements may be effective in slowing the development of fatty liver disease and type 2 diabetes.

From press release:

Animals consuming a high fat diet supplemented with whey protein isolate (WPI) gained 42 percent less weight, and had 32 percent lower body weight than animals fed only the high fat diet, according to findings published in the Journal of Nutrition.

“In mice and humans, high fat diets contribute to the development of insulin resistance and hepatosteatosis, biomarkers and major risk factors for type-2 diabetes and non-alcoholic fatty liver disease (NAFLD),” wrote researchers from the University of Cincinnati and the University of Kentucky.

“In this study, WPI supplementation in mice reduced the severity of several biomarkers, including gain in body weight and adiposity, insulin resistance, and fatty liver,” they added. “[…] whey protein may have therapeutic potential to reduce the incidence of diabetes and fatty liver diseases, especially in at-risk individuals who consume excess energy and fat and lead a sedentary lifestyle.”

Led by Howard Shertzer from the University of Cincinnati, the researchers fed mice a high fat diet for 11 weeks. The high fat diet was defined as providing 40 percent of calories from fat. Animals were subsequently randomly assigned to one of two groups: One groups received normal drinking water, while the other received drinking water containing 100 grams of whey protein isolate (Natural Pure WPI, Bioplex Nutrition) per liter.

In addition to the improvements in body weight and body fat levels in whey protein supplemented animals, compared with non-supplemented animals, the researchers also report that whey-fed animals also had 7.4 percent more lean body mass.

Benefits were also observed in analyses of the animals’ liver showed that whey protein supplementation was associated with 50 percent of the lipid droplet and tissue lipid content of the high-fat only animals,

Dr Shertzer and his co-workers also report that the insulin concentrations of whey protein-fed animals were 29 percent of those recorded in the control animals.

“The protective effect of whey protein was consistent with higher basal metabolic rates and mitochondrial oxygen consumption and lower metabolic utilization of dietary lipid, leading to an overall lower feeding efficiency,” wrote the researchers.

“Because the diets utilized in this study were not isonitrogenous, it is possible that supplementation with any protein would have been effective. Certainly, the active component(s) of whey responsible for these results have yet to be identified,” they concluded.

Study Information

H.G. Shertzer, S.E. Woods, M. Krishan, M.B. Genter, K.J. Pearson
Dietary whey protein lowers the risk for metabolic disease in mice fed a high-fat diet
Journal of Nutrition
2011 April
University of Cincinnati.