Experiments with Golden Syrian hamsters indicated that six week of supplementing a “Western diet” with soy protein led to greater microbial diversity than supplementing with milk protein, and a correlation between these gut microbes and blood lipid levels.
Elaine Krul, PhD, senior technical fellow, DuPont Nutrition & Health and lead researcher on the study, said: “The heart health benefits of soy protein are well-established through numerous clinical and preclinical studies. These results provide insight on how including soy protein in the diet can further support cardiometabolic health through modifying the composition of the microbiome.”
Soy vs dairy
Dr Krul and her co-workers fed 32 male Golden Syrian hamsters a “Western diet” containing 22% milk protein isolate (MPI) as the only protein source for three weeks, and then divided the animals into four equal groups for a further six weeks: The animals continues to consume the same diet but the protein source was 1) MPI, 2) soy protein concentrate (SPC), 3) partially hydrolyzed soy protein isolate (SPI1), or 4) intact soy protein isolate.
Results showed that the soy-fed hamsters had a more diverse microbiota than those fed the milk diet. Gut microbiota profiles from all soy-fed groups were more similar to each other and showed significant differences in abundance of several key microbial families compared to those in the milk-fed group.
In addition, significant reductions in the concentrations of total cholesterol, triglycerides and atherogenic lipoprotein particles were observed with consumption of soy protein compared to milk protein diets.
“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,” said Dr 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.”
Source: The Journal of Nutrition
Published online ahead of print, doi: 10.3945/jn.115.224196
“Soy Protein Compared with Milk Protein in a Western Diet Increases Gut Microbial Diversity and Reduces Serum Lipids in Golden Syrian Hamsters”
Authors: D.N. Butteiger, A.A. Hibberd, N.J. McGraw, N. Napawan, J.M. Hall-Porter, E.S. Krul