There are many reasons why people may gain weight, and not all of them have to do with food intake. For example, weight gain can be a side effect of certain medications, such as steroids or birth control pills. It can also be a symptom of underlying medical conditions, such as Cushing's syndrome or hypothyroidism. In some cases, weight gain may simply be due to genetics or aging. And of course, weight gain can also be the result of overeating or eating high-calorie foods.

However, there are other factors that can contribute to weight gain, and it's important to be aware of all the possible causes. By understanding the various reasons for weight gain, you'll be better equipped to create a weight loss plan that works for you.