LOS ANGELES (CBSLA.com) — Wondering why everyone is wearing red? It’s because Friday is the 15th annual National Wear Red Day to raise awareness about heart disease being the leading killer of women.

The American Heart Association and National Heart, Lung and Blood Institute dedicated the first Friday in February to raising awareness about heart disease and women’s heart health.

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Although heart disease has killed more U.S. women than men since 1984, most medical research has been focused exclusively on men, while women are largely unaware that they are at risk, according to Sally Stewart of Cedars-Sinai Medical Center.

A survey by the American Heart Association found that only one in five American women believes that heart disease is the greatest threat to their health.

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Research has shown that men and women often experience different forms of heart disease. Men who experience heart attacks often feel a tingling in their left arm and chest pain while women’s symptoms may include extreme fatigue, nausea and back pain, Stewart said.

Cedars-Sinai Medical Center will mark the day with its 12th annual Linda Joy Pollin Womens Hearth Health Day with classes on fitness, meditation and Reiki, a Japanese relaxation technique that promotes stress reduction and well being. A panel discussion about new medical discoveries in women’s health will follow.

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