The Importance of Vitamin D

You’ve already heard about taking a vitamin D supplement over winter if you want to keep your bones strong and avoid rickets.

Did you also know that the Institute of Medicine of the National Academies – the government agency that sets those dietary intake numbers that are found on everything from milk to cod liver oil – raised their daily dose recommendation for vitamin D in late 2010 and also took a scientific look at possible uses of vitamin D in the treatment of cancer and other chronic diseases? Here is what they found.

How much is enough?

The Institute’s experts, in their report “Dietary Reference Intakes for Calcium and Vitamin D,” first explained why dietary reference intake (DRI) is a better measurement than the recommended daily allowance (RDA) many of us are used to. They also reported, not surprisingly, that factors of bone health and fracture risk led them to increase the recommended daily intake of vitamin D for people over 70 years of age by 200 IU.

However, the experts gave no definite reason why they also raised the DRI for infants and adults age 50-plus by 200 IU and went up a whopping 400 IU for everyone else despite noting that “[a]t this time, the…data do not…provide compelling evidence that either nutrient is causally related to extra-skeletal health outcomes or that intakes greater than those established in the DRI process have benefits for health.”

They set tolerable upper levels for vitamin D intake, ranging from 1,000 IU to 4,000 IU – many times the new DRI for each age group – and closed their report with “an urgent and worthwhile agenda” of specific research needs, setting out a multi-step research program into possible benefits of both vitamin D and calcium beyond bone health.

Vitamin D research

Prior to the report’s release, Los Angeles pharmacist Christine Gonzalez had taken a look at some ongoing research into possible relationships between vitamin D and chronic diseases and reported her findings in an October issue of the “U.S. Pharmacist.”

In this article, Dr. Gonzalez says that results from many studies into a role for vitamin D in protection from cancer and heart disease are promising but not yet conclusive. She believes that “[o]verall, the evidence is strong in support of supplementing with vitamin D to prevent fractures and falls,” but notes no clear link to immune-system disease or to a risk reduction for influenza, diabetes or depression.

We always look for a magical token that will make bad things go away immediately. Life isn’t like that, but today researchers are hard at work making a science-based assessment of the various health claims made about vitamin D beyond its clearly proven ability to strengthen bones and protect against rickets. Progress is slow but forthcoming, one careful DRI adjustment at a time.

Sources:

Institute of Medicine, Food and Nutrition Board. ” Dietary Reference Intakes for Calcium and Vitamin D. ” 2011. National Academies Press: Washington, D.C. Web. October 6, 2011.

Christine Gonzalez, PharmD, CHHC. ” Vitamin D Supplementation: An Update. ” US Pharm. 2010;35(10):58-76. Web. October 6, 2011.

About the Institute of Medicine .


People also view

Leave a Reply

Your email address will not be published. Required fields are marked *