Poor health of Canada’s South Asians puts their home countries on notice
Wednesday, 1 January 2014 00:05
Genetics, diet and lifestyle are the culprits
Ottawa, Canada: South Asians living in Canada are prone to cardio vascular disease and Vitamin-D deficiency, which is a precursor to bone degenerative diseases, more so than their Caucasian counterparts, a recent study by Health Canada, the country’s federal agency responsible for public health, has found.
And according to one Health Canada scientist, this poor health profile may be extending to their kith and kin of their homelands as well.
“This study has confirmed the information that was out there in the scientific community for some time. That health-wise, we’re poor performers when compared to Caucasians. Sadly, our profile is not a healthy profile,” says Dr. Nimal Ratnayake, a Senior Research Scientist at Health Canada.
The Sri Lankan born Dr. Ratnayake is the head of the Metabolism Section of the Nutrition Research Division at Health Canada. In 2012, Ratnayake spearheaded a major research effort that sought to assess the Vitamin D, Omega-3 and Blood Lipid status of South Asian Canadians, in comparison to Caucasian or white Canadians.
Poorer blood lipid profile
The just-concluded study has found that South Asians have a poorer blood lipid profile compared to Caucasians and showed them to be burdened with lower levels of HDL cholesterol (the good kind), higher levels of triglycerides and higher levels of glucose.
Furthermore, it showed that the Vitamin-D levels in the blood of South Asians were substantially lower than their white compatriots. “We found the levels to be significantly different in comparison to Caucasians. These findings should be of concern to South Asians as a population,” says Ratnayake.
There are about 1.3 million South Asians – Sri Lankan, Indian, Pakistani, Bangladeshi, etc. – living in Canada, amounting to about 4% of Canada’s population. Given the relatively small size of the South Asian population, their poorer health profile is not considered a big social or political problem in Canada. But with recent immigration trends suggesting that the South Asian population is growing faster than any other population in Canada, their health woes may become front page news in the next few years.
“If causes and trends are not identified now, in a few years this population will become a huge drain on Canada’s healthcare system. This is why Health Canada funded our groundbreaking study,” says Ratnayake.
Hailing from Kurunegala and an old boy of St. Anne’s College, Nimal Ratnayake graduated from Peradeniya University in 1972 with Chemistry Honours. He did higher studies at Dalhousie University in Halifax, Nova Scotia and in 1980, received his PhD before joining Health Canada in 1988.
In recognition of his work with health and nutritional effects of dietary fats and oils, in 2013 Dr. Ratnayake was recognised with the Governor Generals award of Commemorative Gold Medal for the Queens Golden Jubilee.
Crucial ingredients for good health
The Health Canada study’s two major components – Vitamin-D and Omega-3 – are two of the most crucial ingredients for good health.
Omega-3 is an important fatty acid primarily present in fatty fish such as salmon, tuna and mackerel. It is a key ingredient in the prevention of cardio vascular disease.
“A higher percentage of South Asians are at risk of coronary heart disease. Diabetic levels among South Asians are significantly higher. It is easy to blame it all on our genetics, but it is primarily due to our diet and lifestyle,” Ratnayake says.
He explains that the South Asian diet, rich in carbohydrates and sugar, coupled with a lack of exercise, seem to have exacerbated a problem that has its roots in genetics. The fact that people have migrated to a western country such as Canada does not seem to have changed their diet, with ethnic foods from their home countries now readily available in the market.
Contributing to the South Asians’ woes is nearly six months of winter weather, which is enough to keep people less physically active and bundled up.
It’s the long winters that prompted the scientists to evaluate Vitamin-D levels, primarily absorbed through exposure to sunlight and not through food. Vitamin-D is considered a huge contributor towards achieving bone health and also in the prevention of cardio vascular disease, hypertension and cancer.
"When we are exposed to the sun and get darker, our skin produces more melanin as a protector. So our capacity to absorb sunlight reduces more and more. This would say that people living in the tropics may not necessarily be absorbing as much sunlight as we think they do. Generally looking at the Sri Lankan population, I can see that we are more prone to bone degenerative disease than white people. In my opinion, the sun is not helping us as much as we think – Dr. Nimal Ratnayake, Senior Research Scientist at Health Canada"
It is a known factor that most people living in northern climates suffer from Vitamin-D deficiency due to the shorter hours of sunlight in winter and with people preferring to stay indoors rather than brave the cold weather. To make up for this deficiency, in Canada for instance, staples such as margarine, milk and juices are fortified with Vitamin-D.
People with darker skin colour, like South Asians, have more melanin in their skin, which slows down the absorption of sunlight. This is a natural protector from the sun for people living in the tropics, but a hindrance for such people who elect to live in wintry climates.
It is estimated that the minimum level of Vitamin-D should be 30 nanomoles per litre, with the ideal level being 50 nmol/l. The study showed that 80% of white Canadians were meeting the ideal standard in winter, while only 47% of South Asian Canadians achieved it. In summer, when there is more than 15 hours of sunlight, white Canadians meeting the ideal Vitamin-D standard increased to 93%. But during the same period, South Asians meeting the ideal standard dropped to 44%.
Says Ratnayake: “This shows that even in the summer, South Asians are not absorbing enough sunlight. Perhaps they are taking unnecessary protection from sunlight. From a health perspective, this is bad news. There is not enough Vitamin-D in the blood (of the South Asian sample) to achieve bone health.”
Lack of sunlight absorption
The lack of Vitamin-D contributes towards the onset of early arthritis, crouching and loss of teeth. Ratnayake points out that such diseases are prevalent amongst people living in South Asia, including Sri Lanka, even though there is no lack of sunlight in this region.
“When we are exposed to the sun and get darker, our skin produces more melanin as a protector. So our capacity to absorb sunlight reduces more and more. This would say that people living in the tropics may not necessarily be absorbing as much sunlight as we think they do.”
He points out that it’s important for South Asian countries to do research on the Vitamin-D levels of their populations.
“Generally looking at the Sri Lankan population, I can see that we are more prone to bone degenerative disease than white people. In my opinion, the sun is not helping us as much as we think.”
According to Ratnayake, the results of his study does indicate that the lack of Vitamin-D levels amongst South Asian Canadians will indeed become a major health issue in the decades to come. He encourages countries like Sri Lanka follow with studies on their own populations to see if the same will hold true for them as well.
(The writer is a former journalist in mainstream media and now lives in Canada. He could be reached via email Mohan.Samarasinghe@rogers.com.)