National Wear Red Day: Number 1 killer of women! What's it about?

The American Heart Association (AHA) celebrates National Wear Red Day on Friday to raise awareness about cardiovascular diseases, the leading cause of death among women.

The American CDC says that coronary artery disease is the most common heart disease — and the leading cause of death for women.

It is caused by plaque in the walls of the arteries that supply blood to your heart and other parts of your body, the CDC says, noting that after menopause, women are at a higher risk of coronary artery disease because of hormonal changes.

The AHA dedicates this day — the first Friday of every February — to spreading the word about the risks and how to prevent heart disease.

The CDC notes that over 60 million women in the United States are living with some form of heart disease.

So what happens on this day? People are encouraged to wear red dresses, post photos on social media, and use the hashtags #wearredday and give.