Researchers also found that soy protein ingredients may reduce concentrations of total cholesterol, triglycerides, and atherogenic lipoprotein particles compared to whey protein.
Photo © iStockphoto.com/Diane Labombarbe
A new study in The Journal of Nutrition compares the effects of whey protein with several soy protein ingredients on gut health and cholesterol in hamsters.
Researchers found that animals consuming one of three Danisco soy proteins from DuPont Health & Nutrition (Wilmington, DE) had a more diverse gut microbiome than hamsters consuming whey protein. Consumption of soy protein was also associated with significant reductions in concentrations of total cholesterol, triglycerides and atherogenic lipoprotein particles.
“The heart health benefits of soy protein are well-established through numerous clinical and preclinical studies,” says Elaine Krul, PhD, author of the study and senior technical fellow at DuPont. “These results provide insight on how including soy protein in the diet can further support cardiometabolic health through modifying the composition of the microbiome.”
The study included 32 golden Syrian hamsters aged 6–8 weeks that were first fed a diet mimicking a typical Western human diet for three weeks, which included 22% milk protein isolate as the single protein source (at 22% by weight). Then, the rats were assigned one of four protein diets for the following six weeks: milk protein isolate, soy protein concentrate, partially hydrolyzed soy protein isolate, or intact soy protein isolate.
Researchers evaluated serum lipids, hepatic gene expression, and gutmicrobial population to determine cardiometabolic effects of the different protein treatments.
Based on sequencing of the 16S ribosomal RNA gene, researchers discovered greater microbial diversity in every soy-fed group than in the milk protein isolate group. All of the soy-fed groups also had lower non-HDL-cholesterol and low-density lipoprotein concentrations than the whey protein group.
Additionally, the soy protein concentrate group presented lower serum total and LDL-cholesterol concentrations than the milk protein isolate group, while the partially hydrolyzed soy protein isolate group presented lower triglycerides concentrations than the milk protein isolate group.
“It has been suggested that increased microbial diversity in the gut microbiome is a marker of cardiometabolic health, where individuals with low richness have a higher incidence of dyslipidemia, adiposity, weight gain, insulin resistance, and inflammation,” says Krul. “Adding lean, high-quality plant proteins, such as soy, to the diet could be a good strategy for individuals seeking products to support health and wellness goals, including weight management with added cardiometabolic benefits.”
Nutritional Outlook Magazine
Butteiger DN et al., “Soy protein compared with milk protein in a western diet increases gut microbial diversity and reduces serum lipids in golden Syrian hamsters,” The Journal of Nutrition. Published online March 2, 2016.