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5 Health Risks of Too Little Sleep

Heart Disease

A University of Chicago study found that inadequate sleep caused levels of cortisol, the stress hormone, to rise in the afternoon and evening-increasing heart rate, blood pressure, and blood glucose. Along with abetting future health problems, the cortisol-induced alertness comes at a bad time-when you should be winding down your day or sleeping. In the same Harvard study mentioned above, researchers found that women who got less than 7 hours of sleep were at slightly higher risk of heart disease too. Sleep deprivation may hurt hearts by raising blood pressure, pumping extra stress hormones into the bloodstream, or raising blood sugar levels.