The Latest on Vitamin D

What you should know about the “sunshine” vitamin.

The Latest on Vitamin D


As we move towards winter and the amount of daily sunshine we receive dwindles, so does our ability to produce vitamin D. And that’s a problem, because vitamin D allows the body to absorb calcium and is critical to bone formation. Without it, kids are susceptible to rickets, a bone-softening disease that results in bowed legs. This disease, once thought to be eradicated, is now making a comeback in Canada.

Vitamin D is called the sunshine vitamin because with just 20 minutes of exposure to the ultraviolet B rays from the sun in fair weather months, our bodies can produce 20,000 IUs of vitamin D – more than enough to keep stores in our body full for awhile. It’s nature’s way of ensuring we get this crucial vitamin, which regulates cell growth, immunity and cell metabolism.

But researchers and nutritionists are finding that many kids and adults are vitamin D deficient – even in summertime. That’s because they stay in the house more or are slathered in sunscreen, which blocks ultraviolet B rays. Also, kids with dark skin can’t absorb ultraviolet B rays as well.

Low levels of vitamin D in kids has also been linked to juvenile diabetes and asthma. In adults, there’s a link between low vitamin D levels and diabetes, cancers, especially breast, prostate, skin and colon, premenstrual syndrome, osteoporosis, depression, Parkinson’s Disease and Alzheimer’s. So making sure everyone in your family gets the right amount of vitamin D is essential.

Health Canada recommends 200 IU per day for people between the ages of 2-50, including pregnant and lactating women. It suggests drinking two glasses of milk (which has been fortified with vitamin D) per day. Adults over 50 should also take a daily vitamin D supplement of 400 IU.

But that may not be enough for optimal health, say experts. In a flurry of articles and reports last year, various experts and groups recommeded that:

  • white-skinned Canadian adults take 1,000 IUs daily in fall and winter and that dark skinned adults should take that amount throughout the entire year (Canadian Cancer Society);
  • adults over 50 should take 800 to 1,000 IUs a day to prevent fractures related to osteoporosis (Osteoporosis Canada);
  • extra vitamin D offers protection against some types of cancer, autoimmune disease, multiple sclerosis and diabetes.

The Canadian Paediatric Society (CPS) also reported in 2007 that many Canadian mothers and breastfed babies aren’t getting enough vitamin D, particularly those in the north. Maternal vitamin D deficiency is associated not only with rickets, but also with smaller sized babies, decreased vitamin D in breast milk, and dental malformations in kids.

CPS recommends that pregnant moms consider taking a supplement of 2,000 IU/day. In addition, all babies who are exclusively breastfed should receive a supplement of 400 IU/day, says CPS. Babies who are at risk of vitamin D deficiency – those with dark skin, who have limited exposure to the sun, or 
whose mothers are vitamin D deficient – should get 

extra vitamin D (800 IU/day) during the wintertime. When babies switch to formula or homogenized milk, they should get enough vitamin D to meet their requirements.

CPS also recommends that research be carried out on vitamin D requirements for toddlers and older children, and on the relationship between vitamin D intake and body mass index. Studies to date indicate that higher levels of vitamin D may be optimal for a child’s health and that vitamin D requirements may vary with weight and BMI.

The 2007 buzz about vitamin D has prompted Health Canada and the U.S. Institute of Medicine to take a second look at their daily recommended values for vitamin D. Their review is ongoing.
So where does that leave concerned parents? Paediatrician Dr. Larry Pancer says that, future studies on the benefits of additional vitamin D aside, “parents who follow Canada’s Food Guide don’t have to worry about vitamin D deficiency.” Dr. Pancer, who sits on the CPS public education subcommittee, suggests that kids get the recommended 200 IU per day in wintertime through diet, first, and supplementation, second.

Vitamin D is found in an assortment of foods – fatty fish like salmon, mackerel and tuna, in liver and egg yolks, and in fortified products, like milk and margarine. Drinking two glasses of milk per day, says Dr. Pancer, will provide most kids with the amount of vitamin D they need.

What if you child doesn’t like milk or fish, is on a restricted diet, or has dark skin? Then use supplements, says Dr. Pancer. If your child is already taking a multivitamin, check the label to see if it is providing 200 IU/day. If not, provide supplements of 200 IU (minimum) to 400 IU (maximum) per day in wintertime. Visit the Canadian Paediatric Society at for more information.

Author: Susan Stanton

Susan Stanton editor and writer.

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