Hidden causes of weight gain

The reason for weight gain isn’t always as obvious as inactivity or a poor diet. Weight gain can stem from many other causes. For example, it might reflect age-related physiological changes such as muscle loss, poor sleep, or changes in sex hormone levels; underlying conditions such as diabetes or sleep apnea; side effects from taking certain medications, such as antidepressants or beta blockers; or possibly the effects of eating late at night or the makeup of gut bacteria. Recent or excessive weight gain warrants a visit to a doctor to help pinpoint the issue.