Get enough sleep.

A study conducted by the University of Chicago Medical Center found that cutting back from the standard eight hours of sleep to four hours each night produced striking changes in glucose tolerance and endocrine function — changes that resembled the effects of advanced age or the early stages of diabetes — after less than one week. Researchers concluded that chronic sleep loss may not only hasten the onset but could also increase the severity of age-related ailments such as diabetes, hypertension, obesity and memory loss.