Why do many cancer patients lose weight?

There are many reasons why patients with malignant tumors often experience emaciation, the main reasons include:

1. Tumor cell growth metabolism: The rapid growth and division of cancer cells leads to an increase in the metabolic activity of tumor tissues. This depletes the patient's body of energy and nutrients, leading to weight loss.

2. Loss of appetite: Cancer patients often have symptoms of loss of appetite, which may be due to the side effects of chemotherapy, radiotherapy, surgery or drugs, and poor appetite will directly lead to insufficient energy and nutrients intake, further leading to weight loss.

3. Consumptive metabolism: Some cancer types produce a state called wasting metabolism, in which the rate of energy expenditure by the patient increases significantly, which may be due to cytokines produced by the tumor and an inflammatory response.

4. Digestive tract problems: Some cancers such as gastric cancer, colorectal cancer, etc., may cause gastrointestinal abnormalities, such as nausea, nausea, vomiting, diarrhea, etc., which can hinder the patient's food absorption and digestion, resulting in significant weight loss and emaciation.

5. Psychological factors: The diagnosis and treatment of malignant tumors may bring great psychological pressure and anxiety to patients, and these mood fluctuations can directly affect appetite or eating behavior.

If your weight drops for no reason, what diseases may be "at fault"?

In addition to the cancers mentioned earlier, wasting can be caused by a variety of reasons, but here are some of the common conditions that can lead to significant weight loss and wasting:

1. Digestive system related diseases: such as gastric ulcer, gastrointestinal inflammation, hepatitis, pancreatitis and other digestive system diseases can lead to poor appetite and malabsorption of nutrients in the body.

2. Metabolic diseases: Diseases caused by metabolic abnormalities such as hyperthyroidism and diabetes may lead to faster metabolism in the human body, consume more energy in the body, and make weight decline significantly.

3. Chronic inflammatory diseases: chronic inflammatory diseases such as chronic kidney disease and rheumatoid arthritis can directly lead to weight loss and emaciation.

4. Psychological factors: Psychological problems such as excessive mental stress, depression, and anxiety disorders will not only affect the patient's mood, but may also lead to loss of appetite and weight loss.

In summary, if you or someone close to you is experiencing unexplained weight loss and wasting, it is advisable to consult a doctor for a detailed physical examination and evaluation to determine the exact cause and get appropriate treatment.

Extended reading: Why do some people binge eat but don't get fat?

排除疾病因素，有些人吃很多但依然不容易長胖，這其實也是可以有很多原因造成的，常見的原因有以下4點：

1. Genetic factors: Some people may have a higher basal metabolic rate due to the influence of their parents' genes, which means that their body consumes more energy at rest, which may make it more difficult for them to accumulate fat.

2. More muscle mass: Compared with fat, muscle tissue is more metabolically active and will also consume more energy. So if a person has more muscle tissue, even if they eat a lot, they may not be so easy to accumulate fat and gain weight.

3. Eating habits: Some people may eat a lot of food, but the food they choose to eat is relatively healthy, containing more fruits and vegetables, high-quality protein and dietary fiber, and less intake of high-sugar, high-salt and high-fat foods, which may help control weight.

4. Activity level: Some people may have a higher activity level, they prefer to engage in physical exercises, or they are engaged in manual labor on weekdays, these activities can help burn extra energy and reduce fat accumulation.