Vitamin D Deficiency

After a recent doctors visit for some routine blood work, I discovered I have vitamin D deficiency. You may be thinking, how can a dietitian be deficient in any vitamin? Well, vitamin D is different from other vitamins because food is generally a poor source.  So, no matter how balanced my diet might be, I can still be deficient. Our skin makes vitamin D when it is directly exposed to sunlight, especially in the summer months.  Sadly, like most people today, I spend most of the day light hours inside the office. And with my fair skin, I try not to expose myself excessively to the sun and when I do I cover up with sun screen. Unfortunately, this has resulted in a vitamin D deficiency.

But, I am not alone, a study from 2007 from the Environmental Health Perspectives Journal, analyzed vitamin D status in three areas of Australia: southeast Queensland, Geelong region, and Tasmania. The results showed that study participants in Tasmania had the greatest prevalence of low vitamin D levels approximately 67.3% of subjects had levels less than 50 nmol/L, followed by those in Queensland (40.5% of subjects), and lastly 37.4% of participants in the Geelong region.

Certain population groups are also more prone to vitamin D deficiency.  People with darker skin do not absorb the vitamin from the sun as well as those with lighter skin.  Also, people who live in colder climates, who have illnesses that prevent proper absorption of nutrients, and breastfed children who do not receive supplemental vitamin D, are all at risk for developing a deficiency. The elderly are also at high risk due to time spent indoors and the skin becomes less efficient at absorbing the vitamin as we age.

Why is vitamin D important?

I am concerned about my vitamin D levels because vitamin D deficiency has been linked to a variety of health problems. People with low vitamin D may experience more bone fractures or muscle weakness, due to the role that vitamin D plays in calcium absorption. Low levels of vitamin D have also been linked to specific cancers such as thyroid, prostate, and breast cancer. Vitamin D is also vital for a healthy immune system and can help us fight off bacteria and viruses, especially in the winter months.  People who are obese tend to have lower levels of vitamin D, as vitamin D is fat soluble and gets trapped in the body’s fat cells.

Treatment of Vitamin D deficiency

The first thing to do if you believe you might be deficient in vitamin D is to ask your doctor for a blood test called 25-hydroxyvitamin D (25-OHD). This specific vitamin D blood level should be ? 70 nmol/L.  For those with a significant deficiency, your doctor may prescribe a high dose of the vitamin temporarily to quickly correct the deficiency. The upper limit of vitamin D is 10,000 IU.

If you want to take an over the counter supplement look for one with Vitamin D3 (cholecalciferol) which more closely matches the type vitamin D naturally found in the body, therefore it is the preferred form for supplementation. If you are deficient, try to take 1000 IU daily to get your levels up, unless otherwise directed by your doctor. Many people may need a “maintenance” level of vitamin D during the winter months of 600 IU. But, the best thing you can do to naturally get your vitamin D levels up is to spend a little time enjoying the sunshine. Just 10-20 minutes of direct sunlight during the summer months will help keep your vitamin D levels up. So get out there and enjoy the sunshine!