Stress can seem relatively benign — after all, everyone experiences stress but it can also have dire consequences. When you consider that chronic stress raises blood pressure and suppresses the immune system, it no longer seems so harmless. The effects of chronic stress on weight aren't harmless either.
While chronic stress can encourage an ever-expanding waistline, acute stress can promote weight loss in some people.
When you're under stress, your body releases so-called stress hormones. Adrenaline makes you feel keyed up, and cortisol stimulates appetite. As a result, people under stress make frequent trips to the fridge and the candy jar. Some people handle stress better than others, and they tend to secrete less cortisol during tense times.
Stress and appetite
A study conducted at the University of Leeds in the United Kingdom found that people who release a lot of cortisol when they're stressed eat more food — hence the reason some people gain weight when they're under pressure and others don't.
Chronically elevated cortisol levels appear to stimulate the growth of fat cells in the abdomen, triggering the worst kind of weight gain (abdominal fat is strongly linked to heart disease and insulin resistance).
The science
In one study, Australian scientists fed stressed and unstressed mice a diet high in fat and sugar and watched the stressed mice balloon twice as much as the unstressed mice. They developed portly bellies and a host of health problems: high blood pressure, prediabetes and high cholesterol.
The reason
In the animals' fat tissue, researchers discovered sharply elevated concentrations of a molecule called neuropeptide Y (NPY), which is released by the body when it's under pressure. NPY unlocks receptors in the fat cells, prompting them to grow in both size and number. The effects of stress appear to be similar in humans.
So relax and remember that exercise reduces stress.
