6 investments in your health

Sure, exercise is good for you. But did you know that just 30 minutes a day can lower your risk of cancer, stroke, diabetes and a host of other ills?

That's without weight loss. If you do drop pounds, the benefits are greater. If you're obese, taking off 10% of body weight can add up to seven months to your life and save you up to $5,300 in lifetime medical costs, according to a study from the American Journal of Public Health.

"Start now. Take a walk," says Dr. Michael Parkinson, head of the American College of Preventive Medicine. "In less than half an hour, you'll be healthier than you were an hour ago."

- Patricia B. Gray is a medical writer and former editor-in-chief of Dartmouth Medical School's Internet Venture.

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