Last updated: Apr 21, 2008
Heart disease
If youre 40-something and overweight—even if you have normal blood pressure and cholesterol— youre much more likely to get heart disease as you get older. Researchers at Northwestern University studied almost 18,000 people for 32 years and found that the obese were 43 percent more likely to die of heart disease later in life than those of normal weight. Fat itself, especially abdominal fat, produces hormones and chemicals that can damage blood vessels, upping the risk of blood clots and diabetes.


Diabetes and kidney disease
The higher your BMI, the higher the risk for these conditions. But according to The Diabetes Prevention Program, which studied people on the verge of diabetes, losing just 7 percent of body weight can cut risk of full-blown diabetes by 60 percent.

Osteoporosis
Extra weight appears to protect women from osteoporosis and fractures by upping bone density. In fact, weight loss of ten percent or more at 50 or older can actually increase the risk of hip fracture in both men and women. “But the number of deaths due to fractures is very small, so to gain weight to prevent osteoporosis is foolish,” says Willett. “Instead, be active, get enough calcium, take vitamin D, and if needed, take medication.”

Cancer
Fat, particularly tummy fat, affects levels of hormones (including estrogen) and growth factors, which in turn appear to spur the development of cancer cells. Fat also hikes the bodys inflammation level, also fanning cancer risk. In fact, this year, the American Institute for Cancer Research and the World Cancer Research Fund linked excess weight to six cancers: breast cancer in post-menopausal women, esophageal, pancreatic, colon, rectal, endometrial, and kidney cancers.