The human heart is a muscle about the size of a closed fist. It works as a pump, sending blood around the body through tubes called blood vessels. The blood carries oxygen from the lungs and food to every part of the body, and it takes away waste. An adult heart beats around 60 to 100 times a minute when the person is resting, and it beats faster during exercise because the muscles need more oxygen. Doctors often check the pulse, the beat you can feel at your wrist, to see how well the heart is working. To keep the heart healthy, experts advise regular exercise, a diet with plenty of fruit and vegetables, and no smoking. Heart disease is one of the leading causes of death in the world, but many cases could be prevented by a healthy way of life.

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