Sleeping too much - or too little - raises the risk of a heart attack, warns major new research. Less than five hours was linked to a 52 percent greater risk of heart attack, while those who slept more than 10 hours a night were at twice the risk. Even for non-smokers who exercise and have no genetic predisposition to cardiovascular disease, skimping on sleep - or getting too much of it - increases the chances of a heart attack, according to the study of more than 460,000 British adults.
The findings, published in the Journal of the American College of Cardiology, also suggest that, for people at high genetic risk for heart attack, sleeping between six and nine hours each night can offset that risk.
On one hand, sleeping too much may increase overall inflammation, but sleeping too little could damage tissue and trigger habits like poor diet that contribute to heart attack risks, the University of Colorado, Boulder, researchers suggest.
The study did not explore the mechanism by which short or long sleep may boost heart attack risk, but previous studies have pointed to a few explanations.
Sleeping too little can impact the lining of the arteries, or endothelium, impact bone marrow development of inflammatory cells, but also lead to poor dietary choices and ill-timed eating - which can in turn impact weight and, also, heart health.
The researchers said that too much sleep may also boost inflammation in the body, which is also associated with cardiovascular disease. They hope their findings will increase awareness about sleep's heart-health benefits.
