Are You "D-ficient"?

As many as one billion people worldwide are thought to have too little vitamin D in their blood. This has become a bigger concern lately. That's because "D-ficiency" is now linked to more than just bone health and muscle strength. Infectious diseases such as tuberculosis and even the flu and common colds may be connected to a lack of this vitamin.¹ And, it's increasingly associated with chronic diseases such as:

• Heart disease
• Certain cancers
• Multiple sclerosis, type 1 diabetes, and other autoimmune diseases
• Osteoporosis
• Parkinson's disease^1,2

            Vitamin D is a hormone your body makes from cholesterol. This is a process triggered by the interaction of sun on skin. Vitamin D is also a nutrient you can get from certain foods such as fatty salmon, tuna, and mackerel. Some foods are fortified with this vitamin. Examples include certain breakfast cereals, yogurt, juice, and milk.³ But it's hard to get enough vitamin D from foods or by being in the sun, especially with concerns about skin cancer. That's where supplements come into play.¹

            If you live at a higher altitude, shun the sun, have darker skin, are obese, or are older, you may be particularly deficient in vitamin D. The only way to know for sure is to have your blood tested.⁴ You can ask your doctor about this.

            In case you've missed it, there's an ongoing debate about how much you need to take to make up for any deficiency. In 2010, the Institute of Medicine (IOM) came out with new recommendations:

• 400 IU for infants
• 600 IU for people ages 1 to 70
• 800 IU for people older than 70¹

            But many scientists still feel this is too low to be fully protective. Doubling or tripling these numbers for those over age 2 may be optimal.¹ Even this may be too conservative. A new study reported that daily intake of vitamin D needs to be somewhere between 1,000 and 2,000 IU to maintain blood levels high enough to prevent major diseases such as cancer.⁵

            Are you considering doses higher than those recommended? Be sure to talk this over first with your doctor, as well as about potential interactions. Vitamin D can interact or interfere with certain medicines or supplements. Examples include prednisone, the weight-loss drug orlistat, cholesterol-lowering drugs and drugs used to control seizures.³

                Which type of Vitamin D is best – vitamin D2 or vitamin D3? Some scientists recommend D3 as it is closer to that produced in your body. However, others say the two are quite similar.  Talk to our pharmacist to help you to decide what is best for you and your family.⁶

                The jury is still out about exactly how much vitamin D you need to prevent serious diseases. But with so much research pointing in the direction of its benefits, surely vitamin D has earned its time in the sun.

Written March 2011

Sources

1. Harvard School of Public Health: "Vitamin D and Health." http://www.hsph.harvard.edu/nutritionsource/what-should-you-eat/vitamin-d/index.html

2. MedlinePlus: "Vitamin D May Precede Onset of Parkinson's." http://www.nlm.nih.gov/medlineplus/news/fullstory_109815.html

3. NIH Office of Dietary Supplements: "Vitamin D." http://ods.od.nih.gov/factsheets/VitaminD-QuickFacts/

4. Harvard School of Public Health: "Comment on the IOM Vitamin D and Calcium Recommendations." http://www.hsph.harvard.edu/nutritionsource/what-should-you-eat/vitamin-d-fracture-prevention/index.html

5. Harvard Website http://www.hsph.harvard.edu/nutritionsource/what-should-you-eat/vitamin-d/index.html#iom-vitamin-d

6. Harvard School of Public Health: "Vitamins." http://www.hsph.harvard.edu/nutritionsource/questions/vitamin-questions/index.html#what-type-of-vitamind