A beer belly is a dangerous thing.
A new analysis of data from a large national study has found that carrying fat around the middle of the body greatly raises the risk for heart disease and death, even for those of normal weight.
Doctors usually determine obesity by body mass index, or B.M.I. — calculated from height and weight — but the calculation does not distinguish between fat and lean muscle weight. Measuring waist-to-hip ratio presents a different, and possibly more accurate, picture because it accounts for central obesity, or visceral fat, the fat stored around the internal organs.
Waist-to-hip ratio is waist measurement divided by hip measurement. According to the World Health Organization, a ratio higher than .90 for men or .85 for women defines central obesity.
It has been known for some time that having an "apple" shape increases the risk for disease and death. But the new study found that a man of normal B.M.I. with an abnormally large belly has an 87 percent higher risk for death than a man with the same B.M.I. but a normal waist-to-hip ratio. Pot-bellied women of normal B.M.I. have a 48 percent higher risk than women with normal B.M.I. and normal belly fat.