Patients with acanthosis nigricans can be combined with diabetes. Acanthosis nigricans is a skin disease with excessive proliferation of skin pigment and warty cells, and can be divided into pseudoacanthosis nigricans and true acanthosis nigricans. True acanthosis nigricans is associated with tumors in the body, while pseudoacanthosis nigricans is associated with obesity, especially in children, and overly obese people are hyperinsulinemic and more prone to diabetes than normal people. Therefore, pseudoacanthosis nigricans often suggests the presence of diabetes mellitus. Obesity can lead to hyperinsulinemia and insulin resistance, resulting in high levels of insulin in the body, and long-term high levels of insulin can lead to insulin resistance, resulting in diabetes. Hyperinsulinemia can also promote cell proliferation and eventually the development of acanthosis nigricans.