By the third exposure to stress, the lean women with abdominal fat still consistently secreted more cortisol in response to stressful lab tasks, compared to women with peripheral fat. Cortisol, in turn may have caused them to accumulate abdominal fat. Genetics, however, also play a role in shaping reactivity to stress, as well as body shape. Lifestyle and age may also influence levels of abdominal fat. Smoking, alcohol and lack of exercise all contribute to greater abdominal fat.
Postmenopausal women tend to carry fat at their abdomen, due to changes in sex hormones.
Epel said a healthy lifestyle, including getting enough sleep, exercise and relaxation, may reduce cortisol levels. However, excess weight on men is almost always stored at the abdomen. On the contrary, in pre-menopausal women, excess weight is more often stored at the hips. Therefore, for women, it is possible that stress may influence body shape more than for men, leading to abdominal fat instead of lower body fat accumulation. Elissa Epel's research team at Yale included Kelly D. Brownell, Ph.D., Jeannette R. Ickovics, Ph.D., Jennifer Bell, and Grace Castellazzo.