Few extra kilos no worry for blokes

There is good news for some men over 50: being just a little overweight is not unhealthy.

But as the scales tip higher - say above 76kg for a 1.7m male - the risk of premature death increases dramatically, according to a study of more than half a million members of the AARP, an advocacy group for US retirees.

Yet for women, there's no late-in-life leeway - being overweight to any degree significantly increases their health risks.

"People who are overweight have a modestly increased risk of premature death," Michael Leitzmann, of the National Cancer Institute and a co-author of the study released this week in the New England Journal of Medicine, said.

"For women, the risk begins immediately when you hit the overweight range, whereas for men you need to travel somewhat higher into the overweight range to hit that increase," said Leitzmann.

The research aims to resolve lingering controversy over whether being overweight carries the same health risks as obesity.

Being overweight is defined as having a body-mass index of between 25 and 30. The BMI is calculated from weight and height. The 1999 Cancer Prevention Study II, funded by the American Cancer Society, found that the death rate rose for those who were both underweight and overweight.

But the federally funded National Health and Nutrition Examination Survey did not find in a 2005 study that being a little overweight or underweight raised health risks.

The problem is smoking, which tends to keep people leaner even as smoking-related illnesses are more likely to kill them.

This distorts the death rates when researchers try to assess the effects of those extra kilograms.

To exclude the effects of smoking, the AARP study looked at the death rates of 186,000 men and women who never smoked and found that that demonstrated the dangers of being overweight.

For a 1.7m male, the highest "normal" weight is now considered to be 72kg. But health risks did not emerge until the scale tipped 76kg for men who had never smoked, the Leitzmann study showed.

Above that, however, the risk of premature death started to increase, sometimes dramatically.

The death rate for men of the same height who weighed 77kg was 9 per cent higher than for those in a group weighing slightly less. It was 20 per cent higher at 82kg, nearly 40 per cent higher at 91kg, 91 per cent higher at 102kg, and more than 2.5 times higher for men above 116kg.

The study was conducted by the National Institutes of Health. A second New England Journal of Medicine study of the weight and mortality rates of more than 1.2 million South Korean adults also found higher risks with extra weight.

"This finding is a sobering reminder that because obesity is now a worldwide problem, the phenomenon of 'global fattening' will contribute to a pandemic of chronic diseases for many years to come," said Timothy Byers of the University of Colorado School of Medicine, in a journal commentary.

- REUTERS