Chapter 8 - Mechanisms Whereby Whole Grain Cereals Modulate the Prevention of Type 2 Diabetes

Abstract

Cereal whole grain (WG) consists of bran, germ, and endosperm in the same relative proportions as the original grains and has a higher dietary fiber bioactive nutrient concentration than refined flour. Observational studies indicate an association between WG intake and type 2 diabetes risk reduction, whereas results from intervention studies are more variable. Dietary fiber components along with bioactives present in WG synergistically contribute to the beneficial health effect not only because of a direct impact on glycemia and insulinemia, but also because of influence on the microbiome and products derived thereof. High-throughput metabolomics analyses have suggested links to betaine, some amino acids particularly branched chain amino acids, and a number of micronutrients and phytochemicals present in WG. However, future research needs to report WG intake in grams, instead of servings or portions and to clarify interactions not only among different dietary factors but also between diet, genetic predisposition, and metabolic determinants.