Obesity is when there is too much fat in the body and is caused by eating and drinking more calories than the body can use. Several things change how many calories (or how much “energy”) people burn each day, for example age, body size, and family history. But one of the easiest changes is how much exercise a person can do every day.
Keeping active can help people stay at a healthy weight or lose weight. It can also lower the risk of heart disease, diabetes, stroke, high blood pressure, osteoporosis [a disease where bones are thin, weak and break easily], and certain cancers, as well as cut stress and boost mood. Not having an active lifestyle does the opposite.
The World Health Organization, the U.S. Dept. of Health and Human Services, and other authorities suggest that adults should get two and a half hours of mild-to-heavy movement each week for good health. Children should get even more, at least one hour a day. There have been some questions among researchers about just how much activity people need each day to keep a healthy weight or to help with weight loss. The most recent studies suggest that a total of two and a half hours a week may not be enough.