Washington: What is the healthiest weight to be? People hoping for a little jiggle room may be disappointed — it is the weight already identified by public health experts using body mass index or BMI.
There had been some suggestion that it may be healthier to be pleasantly plump, but the team at the US National Cancer Institute crushed any such idea with a study of 1.5 million adults published on Wednesday.
The healthiest BMI is 22.5 to 24.9, they found — at the upper end of where the World Health Organisation (WHO), Centres for Disease Control and Prevention and other groups have said people should be.
Body-mass index is the weight in kilogrammes divided by the square of the height in metres. A BMI of between 25 and 30 is overweight and a BMI of 30 or over is obese.
A person 5 feet 5 inches tall (165 centimetres) is classified as overweight at 150 pounds (68 kilogrammes) and obese at 180 pounds. A 5-foot-10 inch (1.8 metres) tall person who weighs 209 pounds (95 kilogrammes) has a BMI of 30 and is obese.
Being overweight or obese raises the risk of heart disease, diabetes, some cancers and arthritis. The study, published in the New England Journal of Medicine, confirms that having a BMI of 25 or more also makes a person more likely to die than someone the same age who is slimmer.
"There is a small increased risk of all-cause mortality associated with being overweight — about 10 per cent compared to having a normal BMI," Amy Berrington de Gonzalez of the National Cancer Institute, who led the study, said in a telephone interview.
Their studies included 1.46 million white adults and 160,087 deaths.
WHO guidelines say the lowest "normal" BMI is 18.5 but Berrington's team found it is not healthy to be too thin. "What we found was that a low BMI — below 20 -- was also associated with an increased risk of death," Berrington said.
