Health care providers have been warning people for years that obesity can lead to serious medical conditions such as heart disease, high cholesterol and diabetes — all illnesses that can kill if left unchecked. But a new study has revealed that there are worse things than being a little overweight. Researchers have found that an inactive lifestyle kills twice as many people as obesity.

For the study, a team of researchers evaluated the medical records of more than 334,000 men and women who were enrolled in a study that looked at the links between cancer and diet. The height, weight, waist size, and self-reported physical activity for each participant were analyzed over a 12-year period, during which time 21,438 participants died.

What the researchers found about the links to health and early death surprised them. They noted that more deaths could be attributed to lack of activity than could be linked to obesity. What's more, researchers found that participants didn't have to exercise for hours at a time to be considered "active." Just 20 minutes of exercise a day, even in the form of brisk walking, was enough to make a difference.

For the study, researchers took into account exercise that came from both recreational and occupational activities. Just over 22 percent of participants were classified as "inactive," because they reported working in sedentary jobs with no additional exercise. Researchers found that those who engaged in even moderate amounts of exercise reduced their risk for early death by 16-30 percent compared to the inactive group. The exercise effect was greatest among those who were not overweight, but the benefit was still noted among overweight and obese participants.

Ulf Ekelund, the lead author of the study and a sport medicine professor at the University of Cambridge, says the message is simple: "just a small amount of physical activity each day could have substantial health benefits for people who are physically inactive."

Sounds like a good reason to go for a walk and shake off the stress of your day.

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Inactivity kills more people than obesity
Just 20 minutes of exercise a day is enough to reduce your chances of early death.