The old man's sudden weight loss means that he may lose more than ten kilograms a month. If weight control caused by deliberately reducing diet or increasing exercise is excluded, sudden weight loss may be related to some common diseases, as follows:

1, malignant tumor, with the increase of age, malignant tumor is likely to develop with the increase of age, and most malignant tumors will lose weight. Therefore, it is suggested to lose weight suddenly, go to the hospital for necessary gastrointestinal endoscopy, abdominal CT and biochemical blood indexes, and rule out the possibility of malignant tumor according to accompanying symptoms, such as nausea, vomiting, abdominal pain and diarrhea.

2. Exclude metabolic diseases, such as hyperthyroidism and diabetes. These two most common metabolic diseases can cause obvious weight loss.

There are many factors leading to sudden weight loss, which are usually caused by abnormal endocrine function and malnutrition. If endocrine function is abnormal, many diseases will occur.

These diseases will lead to the increase of toxins in the body, the destruction of enzymes in the body, the difficulty in absorbing nutrients, or the increase of metabolic rate, which will lead to emaciation and malnutrition, mainly gastrointestinal malabsorption, and it is difficult to absorb nutrients in food.

If the gastrointestinal absorption is not good, you need to eat less and more meals, eat more foods containing vitamins and cellulose, and don't eat spicy, sour and cold foods and junk food. This can improve gastrointestinal absorption, increase gastric acid and absorb more nutrients in food, thus improving the situation of human emaciation.

Diseases with increased metabolic rate can be treated for the primary disease, and the metabolic rate will be normal. There are many reasons why people suddenly lose weight. After going to the hospital for examination at ordinary times, we should treat according to the cause and use drugs according to the doctor's advice.

Therefore, if the average person suddenly loses weight, the first thing to look at is whether the amount of food and consumption are balanced. If there is no big change in diet compared with usual, we should pay attention to whether it is related to illness.