Your body runs on a 24-hour internal clock called the circadian rhythm. This clock controls when your metabolism is fast, when your insulin works best, and when your digestive system is most efficient — and all of these peak in the morning and early afternoon, not at night.
When you eat dinner early, your body processes food during its natural high-performance window. When you eat late, you are forcing your body to handle a large meal at the exact time it is slowing down and preparing for sleep. The result is more fat storage, worse blood sugar, and slower metabolism.