Vitamin D: Do you Really Need to Supplement?

Brooke Bulloch, Registered Dietitian, is a regular guest on Global News Morning Saskatoon.

I came across a headline that made me stop and dig in: 'Stop Taking Vitamin D Already'. What was this all about?? I had to know as it seemed a little too absolute.

Turns out, the article was referring to a recent study published in the New England Journal of Medicine showing vitamin D supplementation did not reduce fracture risk. So is that the end of it? Read on or view my clip from Global News Morning, here.

The Study

The study followed 26,000 relatively healthy US adults >50 years of age for 5 years. They found supplementing with 2000IU vitamin D daily did not reduce total fractures, non vertebral fractures, and hip fractures even in those with low serum vitamin D levels. And this certainly supports other study findings that vitamin D does not prevent fractures.

So, Is Vitamin D Supplementation is Unnecessary?

Here are 4 important considerations:

1) Vitamin D plays an important role in the body, whether or not it prevents fractures.

• Vitamin D is needed for maximum absorption of calcium and phosphorous that enable bone mineralization.
• It prevents rickets in children and osteomalacia in adults (soft, weak bones)
• It supports cell growth, immune function, and glucose metabolism

2) The Recommended Dietary Allowance of vitamin D for ages 1 to 70 years of age is 600IU/day. Few foods naturally contain vitamin D. Food sources include:

• Egg yolks, salmon and sardines, fortified plant beverages, cows milk, and margarine.
• But even the highest source of vitamin D – salmon - provides 250 to 600IU per 3 ounce serving. Majority of my clients are eating salmon only 2-4 times per month, at most. While cows milk offers 100IU/cup, we don’t want toddlers and kids drinking 6 cups daily as this displaces intake of other important food and nutrients.
  

3) While we can make vitamin D in the skin through sun exposure, this is highly influenced by the season, time of day, smog or cloud cover, sunscreen use, and how dark your skin is.

4) We need to consider who is at risk for vitamin D deficiency:

• Breastfed infants
• Older adults (the skin’s ability to make vitamin D declines with age)
• People with limited sun exposure: people who are home bound; people living in nordic latitudes (where solar radiation is not sufficient for vitamin D synthesis for half the year - hello Canada!)
• Chronic conditions such as celiac disease, Crohn’s and colitis, liver disease, PCOS and cystic fibrosis;
• People who have had gastric bypass surgery

Don’t write of vitamin D just yet. There is a good chance you will need a vitamin D supplement if you live in Canada. Speak with your health care provider for advice. If you want to speak with one of our dietitians, find our bios here.