The body-mass index (BMI) - a measure of weight divided by height- is used in the standard method to define obesity. However, according to the experts, East and South Asians were affected by weight-related ill health at a lower cut-off point than in Caucasians.
A BMI of 25 is healthy, more than 25 is overweight and more than 30 obese, according to the World Health Organisation (WHO) guidelines. Many Asians do not fit into this standard, said the Taiwanese academic Pan Wen-Harn at the 10th International Congress on Obesity in Sydney.
According to her, metabolic risks such as hypertension and diabetes are experienced by Chinese, Japanese, Koreans and Indians at a much lower threshold.
The westernisation of the Indian diet and less physical activity are the factors causing metabolic disorders, says Indian researcher Naval Vikram. Genetic make-up is the main reason.
High body fat, a low BMI, high abdominal fat and a low waist circumference are what the Indians are inclined to have. "They suffered hypertension and lipid problems at a BMI of 22 or 23 - much lower than other ethic groups," he said.
"If we use international definitions we will be missing about 15 to 20 per cent of people whom we would be able to identify with a lower cut-off point. That's a substantially large proportion, taking the population of India," said Vikram.
Vikram informed that although proposal for an alteration was made at a WHO meeting in 2004, the region required formal guidelines. "The fact that studies were sometimes not accepted when researchers used Asian-specific measures led many to keep using the universal method in the region," he said.