Malignant tumor: Most malignant tumors will first show emaciation. Therefore, those who have not lost weight in the past but have lost weight recently should be vigilant. For example, pancreatic cancer with faint upper abdominal pain as the main manifestation is often mistaken for stomach disease. The prominent symptom of this disease is obvious weight loss, even exceeding 10 kg within one month. Hyperthyroidism: Hyperthyroidism in the elderly is not as easy to identify as hyperthyroidism in young people. About 1/3 patients have no goiter, and patients above 1/2 have no obvious symptoms, which are mainly manifested as getting thinner and thinner. Chronic infectious diseases, tuberculosis, chronic liver diseases, etc. Many chronic infectious diseases are also common causes of weight loss. Because the body's catabolism is strengthened and the digestion and absorption function is weakened, secondary infection occurs, resulting in excessive consumption of nutrients in the body and obvious weight loss. Hypoadrenocortical function: Some patients with this disease only show emaciation in the early stage, and then gradually appear typical symptoms and signs such as skin and mucosal pigmentation. Gastrointestinal diseases: such as chronic gastritis, peptic ulcer, chronic nonspecific colitis and other gastrointestinal diseases, can cause abnormal eating, poor digestion and absorption function, leading to malnutrition and emaciation. Drug-induced emaciation: This emaciation is often caused by taking some drugs that enhance human metabolism, such as dinitrophenol and thyroxine. It can be seen that if you find that your weight continues to decline for a period of time, you should be vigilant and consult your doctor in time.