A meta-analysis of 13 RCTs (280 middle-aged adults) showed that replacing animal with plant proteins led to modest improvements in glycemic control in patients with T2DM, as the HbA1c, fasting glucose, and fasting insulin were decreased in diets that replaced the animal with plant proteins at a median level of ~35% of total protein per day [168]. This evidence concerns the gene INS and type 2 diabetes mellitus.