However, other studies demonstrated that zinc has different functions in the metabolism of energy and works as a component of several enzymes crucial to the metabolism of carbohydrates, proteins, and lipids and metabolism of hormones that take part in the progress of obesity, especially insulin, and seems to be connected with the mechanisms of insulin resistance usually present among obese people [11, 24–28]. The gene discussed is INS; the disease is obesity due to melanocortin 4 receptor deficiency.