After you fast, when your body releases both insulin and cortisol at the same time, it tells your body to store more fat and stop burning it—like hitting the pause button on fat loss.

Chronic elevation of cortisol preferentially promotes central adiposity due to the higher density of glucocorticoid receptors in visceral adipose tissue compared to subcutaneous depots.

When you don't eat for about 3.5 days, your body switches to burning fat for energy—so it stops listening to the hormone that tells fat cells to stop breaking down, and starts listening more closely to the hormone that tells them to break down faster.