Nutrition & Diet

You may have noticed the press about Vitamin D lately and wondered what all the interest is in a vitamin (actually a hormone) that has been around for a long time.  There are two types of Vitamin D, D2 and D3.  D2 comes from the diet or supplements, and D3 is produced in the body through sunlight exposure.  There are several debates about why children and adults are testing increasingly low for Vitamin D and there are even debates about the correct way to test blood serum levels for a deficiency.  As always, I encourage you to read up and research multiple sources so you can make your own decision about whether not you should be tested or take Vitamin D supplements.  Here is a link for a pretty comprehensive article about the current controversy surrounding Vitamin D: http://www.nbcbayarea.com/health/dietfitness/SheddinglightonvitaminDdeficiencycrisis.html

Vitamin D is needed to maintain proper levels of calcium and phosphorus in the blood helping to form and maintain strong bones but adequate levels are also necessary for many functions in the body ranging from bone, digestive, brain, respiratory and immune health.  In the 1930’s we began fortifying our milk products with Vitamin D in response to rickets, a bone disease seen in children.   While rickets is rarely seen in the U.S. now, it is believed that deficiencies in Vitamin D still exist in both children and adults possibly contributing to other diseases.  Some of the research suggests that deficiencies take a long time to show up in the body which may be why we’ve missed the correlation of low levels of Vitamin D to conditions other than bone related disease such as osteoporosis.

Exposure to sunlight is an important source of Vitamin D and UV rays from sunlight trigger the synthesis of Vitamin D that is then stored in the body.  Many of us limit our exposure to sunlight due to skin cancer fears and/or we slather on sunscreen rather than expose our skin to the aging effects of the sun.  Sunscreen with a SPF of 8 or greater will block UV rays that produce Vitamin D.  Here is a lengthy but very interesting article about the different UV rays and why regular brief exposures to mid-day sun may be the best way to boost Vitamin D levels.  It’s interesting to note that Vitamin D is only stored in the body for 1-2 weeks following sun exposure. http://www.westonaprice.org/basicnutrition/vitamindmiracle.html

Currently I recommend that my patients have their Vitamin D levels tested or consider supplementing with 2,000 IU’s of D3, particularly if you are avoiding the sun or we are moving into cooler months.  Additionally, brief, regular sunbathing for 20 minutes is recommended between the hours of 10 am and 2 pm – without sunscreen!