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Aim for Your Optimal Weight
Sticking close to your teenage weight is good for your health and your vanity. Gaining a lot between the ages of 18 and 40 is particularly dangerous because "every 10 percent increase in weight raises blood pressure, and high blood pressure is one of the major factors affecting aging," says Dr. Roizen. Plus, lowering your daily caloric intake by 10 to 20 percent seems to be linked to a longer life, says Dr. Terry Grossman, co-author of Transcend: Nine Steps to Living Well Forever.