best doctors in yelahanka There are several reasons for weight gain, often categorized into lifestyle, medical, and psychological factors. Here are some key reasons: Dietary Habits: Overeating, especially foods high in sugar, fats, and processed ingredients. Excessive calorie intake without enough physical activity. Lack of Physical Activity: Sedentary lifestyle, such as sitting for long hours at work or home, leads to burning fewer calories than consumed. Medical Conditions: Hypothyroidism: An underactive thyroid gland can slow metabolism. Cushing's syndrome and Polycystic Ovary Syndrome (PCOS): Hormonal disorders that affect weight. Certain medications, including antidepressants, antipsychotics, and corticosteroids, may cause weight gain as a side effect. Genetics: Genetic predisposition can make some people more likely to gain weight.