Vitamin D: Bone health and more!

For decades, we have known that vitamin D builds stronger bones by helping your body absorb calcium. Recent research suggests that vitamin D may also decrease your risk for breast, prostate, and colon cancer.

 “Besides helping to prevent osteoporosis, there is strong evidence from the last five to 10 years that maintaining your levels of vitamin D actually helps to reduce cancer,” says Heather Chappell from the Canadian Cancer Society.

 “We still don’t know what the optimal vitamin D levels are or how it works to prevent cancer, but the relationship is there,” she says.

Vitamin D is often called the “sunshine vitamin” because under the right conditions in the sun, the skin can produce its own vitamin D. However, during the winter, people in Canada produce very little vitamin D. The sunlight is too weak and we need to wear a lot of clothing.

Even in the summer, people may not get enough
vitamin D:

  • Sunscreens and sun-protective clothing block the skin from producing vitamin D.
  • Dark skin does not produce vitamin D as efficiently as lighter-pigmented skin. Adults with highly pigmented skin need 10 to 20 times more sun exposure to make the same amount of vitamin D.
  • Older adults do not create vitamin D from sunlight as efficiently as younger people do. They may also spend less time outdoors.  

Getting vitamin D through food and supplements

For these reasons, many health organizations suggest that you increase your vitamin D intake through diet, supplements, or both. Food sources of vitamin D include fortified foods, such as cow’s milk and soy or rice beverages. Margarine and fish, such as salmon and tuna, are also good sources of this vitamin.



Vitamin D: Bone health and more!

Eating Well with Canada’s Food Guide advises people over the age of 50 to take in three servings of milk or fortified soy beverages a day. It also recommends a supplement of 400 IU (10 micrograms) of vitamin D every day.

“It’s very hard to get enough from what you eat,” says Dr. Kerry Siminoski, a specialist in bone disorder and bone health at the University of Alberta. “Liver is a source, but when is the last time someone told you they were eating liver for dinner? Or creamed salmon five days a week? With supplements, you ensure that you get what you need without short-changing your other nutritional requirements or exceeding your caloric intake.”

How much is too much?

Because the benefits of vitamin D go beyond bone health, several organizations recommend taking more than Health Canada does. Despite the potential benefits, Health Canada cautions that high doses can be toxic. However, if you want to take between 1,000 and 2,000 IU of vitamin D a day (from food and supplements combined), you should be safe. “There’s a huge safety margin for vitamin D as opposed to calcium,” says Dr. Siminoski.

Talk with your doctor, pharmacist, or dietitian to see if you could benefit from a daily vitamin D supplement.

Adapted with permission from

Click Here for PDF print file