Why can't I gain weight no matter how much I eat? Why am I still thin

It may be related to gastrointestinal absorption disorder, hyperthyroidism, diabetes, chronic consumptive diseases, mental stress and other factors. Long term abnormal weight loss requires vigilance against pathological causes, and it is recommended to seek medical attention and investigation in a timely manner.

1. Gastrointestinal absorption disorders

Chronic gastritis, irritable bowel syndrome and other digestive system diseases can lead to nutrient malabsorption. When gastric acid secretion is insufficient or the gut microbiota is imbalanced, the protein, fat, and other nutrients in food are difficult to fully break down and utilize, which may lead to normal appetite but sustained weight loss. These patients often experience discomfort such as bloating and diarrhea, and a clear diagnosis should be made through gastroscopy examination.

2. Hyperthyroidism

Excessive secretion of thyroid hormones can accelerate metabolism and put the body in a high consumption state. Although the patient's food intake has increased, their weight has sharply decreased, accompanied by symptoms such as palpitations, hand tremors, and fear of heat and excessive sweating. The diagnosis of hyperthyroidism requires testing the levels of thyroid stimulating hormone and free thyroxine in the blood. Delaying treatment may lead to hyperthyroidism heart disease.

3. Uncontrolled diabetes

Type 1 diabetes or uncontrolled type 2 diabetes will lead to impaired glucose utilization, and the body will turn to the decomposition of fat and protein for energy supply. The typical manifestation is weight loss due to excessive drinking and eating, and some patients may experience acute complications such as ketoacidosis. Blood glucose monitoring and glycated hemoglobin testing are important diagnostic criteria.

4. Chronic wasting diseases

tuberculosis, malignant tumors and other wasting diseases will cause progressive wasting. Cancer cell proliferation can plunder a large amount of nutrients, while tuberculosis infection can cause long-term low-grade night sweats. This type of disease may only manifest as unexplained weight loss in the early stages and requires imaging examination and pathological biopsy for diagnosis.

5. Psychological factors

Long term anxiety and depression may affect digestive function through neuroendocrine pathways. Continuous elevation of stress hormones can inhibit gastrointestinal motility, and some individuals may experience anorexia nervosa or malabsorption after eating. The combination of psychological assessment scales and hormone testing can help distinguish this type of non organic emaciation.

It is recommended that individuals with abnormal weight loss record daily dietary calories and weight changes, and prioritize screening for digestive and endocrine diseases. High calorie healthy foods such as nuts and avocados can be added appropriately, combined with impedance training to promote muscle synthesis. Avoid taking weight gain drugs on your own. Hyperthyroidism or diabetes patients should strictly follow the doctor's advice. Regularly monitor body mass index. If the weight loss exceeds 10% within six months or is accompanied by other symptoms, seek medical attention immediately at the endocrinology or gastroenterology department.