Evidence reviewed in our paper indicates that regulation of blood glucose concentrations may involve several positive effects exerted by SCFAs occurring at different levels (Figure 1): (i) the decreased inflammatory state that reduces insulin resistance, (ii) the contemporarily increased GLP-1 secretion that stimulates insulin release, and (iii) the improved beta-cell function that contribute to amelioration of glucose homeostasis. This evidence concerns the gene GCG and Insulin resistance.