Hello, first we need to know what hypothyroidism is. This disease is caused by insufficient secretion of thyroid hormone. Once you get this disease, it is a lifelong disease. Thyroid hormone itself has the function of regulating metabolism. When you suffer from hypothyroidism, the thyroid hormone secreted by your body decreases, which affects your body function, leading to a decline in metabolism and weight gain. If you want to lose weight, you must first treat hypothyroidism and control your condition.