Diet restriction that improves longevity and health span also modifies gut microbiology

Abstract

The importance of gut microbiota in gut health and health in general has received considerable attention. The elderly are known to have reduced diversity and decreased relative abundance of desirable microbiata. These age‐related changes in gut microflora could diminish health span. For example, reductions in the relative abundance of important sub‐populations such as Clostridium cluster IV and bifidobacteria might result in reduced formation of short chain fatty acids, altered epithelial cell maintenance, and altered barrier function of the gut epithelium in the elderly. Those changes in the GI microbiota have previously been linked to impaired immune function prevalent in older individuals and may result in a greater susceptibility to disease. It is well established that diet restriction leads to improved health and increased longevity in many species. In addition, resistant starch diets improve gut function and metabolic status. Does part of this increase in health involve an improvement in gut function and specifically in gut microbiota? The data from 2‐year old C57BL/6 mice fed either resistant starch or were diet restricted show similar trends for the bacteria levels measured by qRT‐PCR. Both treatments increase Bifidobacterium and total Clostridium IV. These data support our hypothesis that dietary fermentable fiber mimics many of the effects of diet restriction on health span and longevity. Supported by National Starch and LSU AgCenter.