There are several postulated mechanisms for the effect of sleep curtailment on development of insulin resistance as well as for predisposition for Type 2 diabetes: increase of sympathetic neuronal activity, decreased cerebral utilization of glucose, increase in evening cortisol values, growth hormone increase and disorder of neuroendocrine control of appetite which increases the risk for getting the body weight [26]. This evidence concerns the gene GH1 and type 2 diabetes mellitus.