Packing on pounds riskier for South Asians

It's not fair, but it's true. A new study by researchers at McMaster University has found that some ethnic groups are more likely to be adding dangerous fat onto their internal organs like their liver when they gain weight, while others just add it to their waistline.

Dr. Sonia Anand, who led the study published today in the medical journal PLoS ONE, said South Asians are particularly more likely to add the type of organ-hugging fat that can lead to diabetes and coronary artery disease.

Previously the researchers at McMaster and the Population Health Research Institute had found that, even with the same body mass index as white Caucasians, people who originate from the Indian subcontinent have more risk factors for cardiovascular disease including type 2 diabetes, low "good" or HDL cholesterol, and more abdominal obesity.

"The new study showed South Asians have less space to store fat below the skin than white Caucasians," said Anand, a professor of medicine and epidemiology at McMaster University. "Their excess fat, therefore, overflows to ectopic compartments, in the abdomen and liver where it may affect function."

This visceral fat, she added, is associated with metabolic problems such as elevated glucose and abnormal lipids which are risk factors which ultimately lead to coronary artery disease.

The study was sponsored by the Heart and Stroke Foundation of Ontario. Anand holds the Heart and Stroke Foundation of Ontario/ Michael G. DeGroote Chair in Population Health Research.

"Many Canadians of South Asian descent – as well as those of Aboriginal, African and Chinese descent – are experiencing historic levels of risk for heart disease and stroke. It is only through research like this that we can learn how better to treat and prevent these diseases, so lives are not cut short," said Mary Lewis, vice-president, research, advocacy and health promotion of the Heart and Stroke Foundation of Ontario. "The Heart and Stroke Foundation of Ontario is proud to support such important work."

Dr. Arya Sharma, director of the Canadian Obesity Network and a co-author of the study said: "This study helps explain why South Asians experience weight-related health problems at lower BMI levels than Caucasians. For the clinician, this also means that individuals of South Asian heritage need to be screened for the presence of heart disease and diabetes at lower BMIs."