BMI, girth best indicate obesity health risks

NEW YORK, Aug 31 (Reuters) Simple measures like a person's body mass index (BMI) and waist circumference are adequate to gauge their health risks due to excess weight, at least among older men, UK researchers conclude.

BMI is a measure of weight in relation to height. Questions have been raised as to whether this or waist measurements can accurately convey the contributions of lean body mass and fat mass to health, Dr Sheena E Ramsay of the Royal Free Hospital and University College Medical School in London and colleagues write in the American Journal of Epidemiology.

Measuring a person's percentage of fat and lean mass requires fairly complex tests -- for example, bioelectrical impedance analysis, which involves measuring how electricity is conducted through the body.

To better understand the relationship of various measures of obesity and body fat levels to health and disability, Ramsay and her colleagues looked at 4,252 British men between the ages of 60 and 79.

BMI, waist circumference and fat mass index were all closely related to one another, the researchers found.

Increases in these measurements were linked to disability, poor health, and risk factors for heart disease and diabetes such as high blood pressure and low levels of ''good'' cholesterol.

While having a low fat-free mass index was tied to an increased risk of cancer and poor respiratory function, this measurement had no independent relationship to other measures of health or disability.

''It is clear in our study that measures of body fat, such as body mass index and waist circumference, are good indicators of adverse health outcomes,'' the researchers write.

They conclude: ''Using these simple measures of adiposity should be encouraged to reduce the public health burden of obesity and overweight in the elderly, by the promotion of lifestyles that decrease the weight gain accompanying the aging process.'' REUTERS MS BS0859