A diet supplemented with soy protein may be an effective adjunct therapy for inflammatory bowel diseases, Penn State researchers reported after completing a study that included mice and cultured human colon cells. The findings are significant because inflammatory bowel diseases affect nearly 4 million people worldwide and have an economic impact of more than $19 billion annually in the United States alone.
Joshua Lambert, associate professor of food science in the College of Agricultural Sciences said his team found that soy-protein concentrate can exert antioxidant and cytoprotective effects in cultured human bowel cells and can moderate the severity of inflammation in mice that have an induced condition similar to ulcerative colitis.
Zachary Bitzer and Amy Wopperer, former graduate students in the Department of Food Science and the lead researchers, substituted soy-protein concentrate into the diet of the mice and removed corresponding amounts of the other protein sources, equaling about 12 percent. They kept human equivalents in mind as they determined the amount. The dietary soy-protein concentrate at the 12-percent dose level ameliorated body-weight loss and swelling of the spleen in the mice with induced inflammatory bowel disease.
Results of study in mice and cultured colon cells are published in The Journal of Nutritional Biochemistry. Next step is finding if these results are reproducible in Humans. Lambert believes human studies could be arranged in the near future. Lambert’s laboratory soon will start a related investigation of whether the inflammation-moderating effects triggered in the mouse colons are due solely to the soy protein or also may be caused by soy fiber. Soy-protein concentrate is 70 percent protein by weight, but it also has quite a bit of soybean fiber in it, he explained.
Research Funding: Pennsylvania Soybean Board, American Institute for Cancer Research, US Department of Agriculture’s Hatch Program.
Adapted from press release by the Penn State University.