What does chronic stress do to your weight in the long run?

Chronically elevated cortisol levels push your body toward weight gain over time. Cortisol, the hormone that drives your stress response, promotes fat storage while simultaneously impairing normal blood sugar regulation. Prolonged exposure to it is even explicitly listed as a known side effect in people who take corticosteroid medications for extended periods for medical reasons.

Beyond increased fat tissue, persistently high cortisol raises the risk of insulin resistance and, ultimately, type 2 diabetes. The concern is not just about the number on the scale: the fat preferentially accumulates around the abdominal organs. Visceral fat, as this type is called, is more dangerous than fat elsewhere on the body and increases the risk of cardiovascular disease.

Fat tissue is itself a source of inflammation. When you carry excess weight over a long period, fat cells secrete more inflammatory substances, including compounds that further fuel insulin resistance and cardiovascular problems. A study in young adults around the age of 30 showed that people who had been overweight since childhood had higher inflammatory markers in their blood and signs of accelerated biological aging. This was an association study, not proof of a direct causal chain.

Chronic stress combined with eating behavior makes the picture more complicated. Stress promotes overeating and a sedentary lifestyle, which independently increase visceral fat and insulin resistance. There are also indications that prolonged elevated cortisol can erode muscle mass, although that aspect is less well quantified in the available research.