When it comes to your health, does it matter if you’re black or white? With mounting evidence suggesting waist circumference (WC) is more important than weight when it comes to assessing disease risk, more emphasis is being placed on determining what, exactly, is a healthy waist size. (And no, this doesn’t mean pants size; see the end of this column for instructions on measuring your own WC.) But for many Canadians of non-European descent, the current targets don’t measure up, and a new study suggests this could lead to serious health consequences.
SOUTH ASIAN RISK
According to the study, conducted by researchers at McMaster University, weight gain among individuals of South Asian descent was found to be more harmful than for other ethnic groups. When South Asians gained the same number of pounds as their non-South Asian counterparts, they gained a higher percentage of what is known as visceral fat, or the type of fat that accumulates around organs. A higher amount of visceral fat not only leads to a thicker waist, but it also increases risk of heart disease and Type 2 diabetes. Subcutaneous fat, by contrast, is the fat located under the skin, and is less associated with disease.
The findings confirm previous research suggesting South Asians are at a disproportionately high risk of heart disease, and that the risk seems to be linked to gains around the waist. But what about other non-Caucasian ethnic groups? According to the Health Canada website, “a WC at or above 102 cm (40 inches) for men, and 88 cm (35 inches) for women, is associated with an increased risk of developing health problems such as diabetes, heart disease and high blood pressure.” That would be true if all Canadians were white, but it does not reflect this country’s growing ethnic diversity.
DIVERSE RISK FACTORS
According to the 2006 Canadian clinical practice guidelines on the management and prevention of obesity in adults and children, optimal waist circumference for individuals of European descent is less than 94 cm (37 inches) for men and 80 cm (31.5 inches) for women. While these numbers are lower than the targets listed by Health Canada, you can think of them as the optimal target, whereas the Health Canada numbers reflect the high risk cutoff. But the 2006 guidelines go a step further by including specific recommendations for Japanese, South Asian and Chinese populations, as well as workarounds for South and Central Americans and Sub-Saharan African and Arab populations (see the table below for full recommendations).
THE BOTTOM LINE
In a nutshell, this new research, coupled with a handful of existing guidelines, tells us that, when possible, we need to avoid generalizing when it comes to talking about weight gain among different ethnic groups. If you are of Japanese, Hispanic, Malaysian or Pakistani descent, your risk associated with weight gain may be higher than what the charts at your doctor’s office say.
For now, however, many, if not most of the published guidelines for the prevention and management of weight-related diseases (Type 2 diabetes, heart disease, and cancer being the big three) do not differentiate between ethnic groups, so educating yourself about your own risk factors is important. With that in mind, here are a few tips to help understand and manage your risk of weight-related disease:
• To take your own WC, find the lowest point on your ribs and the top of your hip bone. Place a tape measure around your waist at the midpoint between the two points (even if it isn’t where you wear your pants), and make sure the tape measure is flat. Take your measurement after a normal exhale.
• If your WC is outside of the optimal range (don’t worry, you’re not alone), you can use a rough guideline that every five pounds you lose or gain will affect your WC by about one inch.