The Year in Medicine 2008

Troubled sleep can cause problems for anyone, but for women, the consequences may be even more dire. In a study of 210 men and women, Duke University researcher Dr. Edward Suarez found that women who slept poorly had elevated levels of several risk factors for heart disease and diabetes — including cholesterol, insulin, glucose, inflammatory proteins and the clotting agent fibrinogen — but men who tossed and turned did not. The reason may have something to do with testosterone. Men who reported the most difficulty sleeping also had the highest levels of testosterone, which is known to reduce concentrations of heart-damaging inflammatory proteins. It's not certain if testosterone somehow contributes to the sleeplessness or if it's somehow released protectively in men who don't get enough z's. No matter such details; for both sexes, better sleep will almost always mean better health.