Diabetes is a common and serious disease. Many gerontologists believe that diabetes is a sign of aging. 1 type diabetes mellitus mostly occurs in young people and belongs to insulin deficiency type, accounting for 10% of the total number of diabetic patients. Type 2 diabetes, which is also the most common, mostly occurs in the elderly. It is caused by insufficient insulin secreted by the pancreas, which leads to hyperglycemia, affects the whole body, and can cause damage to the circulatory system, leading to blindness, cataract, stroke, liver and kidney damage, nervous system diseases, infection, sleep and other problems and high cholesterol.

Scientists compared the amount of melatonin secreted by the pineal gland of diabetic patients and normal people of the same age, and found that the amount of melatonin secreted by diabetic patients at night was lower than that of normal people. This may be due to the functional decline of the pineal gland. During sleep, the human body will secrete various hormones, including growth hormone, which will increase the blood sugar level. Melatonin, which is also secreted at night, can regulate the secretion of growth hormone and keep it within the normal range. A study showed that by supplementing metoclopramide, the insulin and blood sugar of mice returned to normal levels. Scientists believe that the supplement of Merlotone seems to prevent the development of type 2 diabetes.

Stress caused by external pressure can promote the secretion of a corticosterone called stress hormone and raise blood sugar level. In daily work and life, these excess blood sugar will exist in the blood for a long time. Melatonin controls the secretion of corticosterone, thus helping to reduce the possibility of type 2 diabetes.