One in 10 Canadians isn't getting enough vitamin D, Statistics Canada reports in its first study to ever attempt to measure levels of the vitamin in the blood of Canadians.
The new data, released Tuesday, finds that 10 per cent of Canadians, or roughly 3 million people, have "inadequate" concentrations of the nutrient.
Four per cent of Canadians have vitamin D levels so low, they are considered vitamin D deficient, a serious condition that can cause rickets in children and osteoporosis in adults.
"Vitamin D is a nutrient that helps the body use calcium and phosphorus to build and maintain strong bones and teeth. When it is deficient, the body absorbs very little calcium," the agency notes in a news release accompanying the new report.
"Deficiency in children can cause nutritional rickets, a condition that results in soft bones and skeletal deformities. In adults, low levels of vitamin D can cause osteoporosis."
The report found that the highest rates of vitamin D deficiency are found among men aged 20 to 39, with about 7 per cent of them considered fully deficient in the vitamin.
But the study authors note that that a debate is underway about what levels of vitamin D are considered optimal for good health.
For the purposes of this study, vitamin D deficiency was defined as a concentration below 27.5 nanomoles per litre (nmol/L). Vitamin D inadequacy for bone health was defined as a concentration below 37.5 nmol/L.
Those standards were set in 1997 and are currently getting a second look.
"These recommendations are currently under review by both Canada and the U.S.," Statistics Canada research analyst Kellie Langlois told CTV News.
Concentrations above 75nmol/L have recently been proposed for optimal health.
Using that measure, the survey that found only one-third of the population (33 per cent of males and 37.8 per cent of females) had optimal levels of the vitamin. Still, that may be better than many expected.
"Without being able to make direct comparisons with other countries, we don't seem to be doing too bad," Statistics Canada research analyst Kellie Langlois told The Canadian Press.
"In Canada there's a lot of talk that we're at higher latitudes and we're already kind of at a disadvantage. But there are 35 per cent of people making this. So it is possible."
While vitamin D can be found in milk products and fish, most people don't get enough through diet alone. The vitamin can also be absorbed from sunlight in the summer months, but for a large part of the year in Canada (October to March, and longer in far northern latitudes) the sun is not strong enough to produce vitamin D in the skin. The skin also has reduced capacity to produce vitamin D as it ages.
With a wealth of recent research suggesting strong links between vitamin D and reduced risk of cancer, the Canadian Cancer Society decided to recommend in 2007 that white Canadians take 1,000 IU (International Units) of the vitamin a day through the fall and winter, and those with dark skin to take it year-round. (Non-whites don't make as much of the vitamin, even with long exposure to the sun.)
"We know that 800 or 1,000 IU is the bare minimum to give you sufficient blood levels of this vitamin to give you protection from these diseases," Dr. Richard Kremer, an endocrinologist at McGill University Health Centre, told CTV News.
2 in 5 Canadians have high cholesterol
In related health news, Statistics Canada also found that 41 per cent of Canadian adults have high cholesterol, which can cause high blood pressure.
About 36 per cent of adult Canadians had unhealthy levels of "bad" LDL cholesterol, while 30 per cent had unhealthy levels of HDL cholesterol.
The study found that about 27 per cent of adults aged 20 to 39 had high levels of total cholesterol from 2007 to 2009. This percentage increased to 47 per cent among those aged 40 to 59 and 54 per cent of those aged 60 to 79.
The report also found that about 25 per cent of Canadian adults had unhealthy levels of triglycerides. This percentage also increased with age, from 17 per cent among adults aged 20 to 39 to 34 per cent among the age group 60 to 79.
Unhealthy levels of total cholesterol, triglycerides, and bad cholesterol are generally associated with higher rates of high blood pressure and can lead to heart disease.
All of the findings are from the Canadian Health Measures Survey, a survey of 5,600 Canadians that launched in 2007 to collect key information about the health of Canadians using direct physical measurements, such as through blood and urine samples, and blood pressure and weight measurements.
With a report by CTV's Genevieve Beauchemin in Montreal
