Researchers at Washington University School of Medicine in St. Louis have identified ingredients for snack food prototypes that have been formulated to deliberately change the gut microbiome in ways that can be linked to health.
Translating results from animal models, the scientists have shown in two pilot human studies of overweight participants that snacks containing combinations of specifically selected fiber types affect elements of the microbiome involved in metabolizing fiber components. This shift in the microbiome was linked to changes in groups of blood proteins that are biomarkers and regulators of many facets of physiology and metabolism. These blood proteins shifted in ways that could improve health in the long term.
The study is published June 24 in the journal Nature.
“Poor nutrition is a pressing and complex problem worldwide that is driven by many factors, including an overabundance of high-fat and low-fiber foods in typical Western diets,” said the study’s senior author Jeffrey I. Gordon, MD, the Dr. Robert J. Glaser Distinguished University Professor and director of the Edison Family Center for Genome Sciences & Systems Biology at Washington University School of Medicine. “Since snacks are a popular part of Western diets, we are working to help develop a new generation of snack food formulations that people will like to eat and that will support a healthy gut microbiome that affects many aspects of wellness.”
The human intestine is home to a microbiome composed of tens of trillions of microbes containing millions of different genes that perform functions that are not provided by the approximately 20,000 protein-coding genes in the human genome. According to the researchers, the nutritional value of foods is determined in part by the products of the foods’ unique metabolism by the gut microbiome.
Gordon and his colleagues are focused on characterizing which food components interact with which components of the gut microbiome and how this interaction shapes different features of human biology. The goal is to herald a new era of nutritional science that yields affordable, more nutritious foods from sustainable sources that can be used to treat or prevent various forms of malnutrition — whether it be undernutrition or obesity in children or adults.
The high-fat, low-fiber diets consumed in the U.S. and other Western countries fail to support a diverse and healthy gut microbiome. Moreover, diets with high fiber content are associated with lower risks of chronic diseases such as cardiovascular disease, type 2 diabetes and obesity. However, dietary fibers are composed of complex and diverse mixtures of biomolecules, many of which the human body can’t break down on its own. The nature of these mixtures varies depending upon the source of the fibers and how they are processed when incorporated into foods.