THE TRUTH
ABOUT VITAMIN D
By Dr. Darren Snodgrass
Vitamin D is a
fat-soluble vitamin that has recently garnered much media attention. The difficulty with Vitamin D is that it is
naturally present in very few foods.
It is made in our bodies when our skin
is exposed to ultraviolet rays from the sun.
This Vitamin D is initially biologically inactive. It then gets converted by the liver to form
an active form of Vitamin D, also known as calcidiol. Some of the calcidiol is converted in the
kidney to form another physiologically active form of Vitamin D, also known as
calcitriol.
Vitamin D has a multitude of functions
in the human body. It promotes calcium
absorption in the gut, helps with bone growth/remodeling, and reduces
inflammation.
Current research shows that Vitamin D
is involved in the regulation of over 200 genes responsible for cellular
growth, differentiation, cell death and blood vessel generation. The cell health genes are especially
important when it comes to considering the anti-cancer effects of Vitamin D.
The best marker to check for Vitamin D
status is done via a blood test by your doctor. The optimal level is greater
than or equal to 30ng/ml.
Inadequate intake of Vitamin D is a
leading contributor to osteoporosis, which affects 10-12 million Americans.
The people at most risk for Vitamin D
deficiency include: elderly people;
people with dark skin tones, who may require as much as six times the UV light
to produce Vitamin D; obese patients, whose fat tissue sequesters the Vitamin
D; and breastfed babies who receive small amounts of vitamin D from breast
milk.
The
current U.S. recommended daily allowance for vitamin D is as follows:
¨
Birth – Age 50: 200
IUs/day (update: new guidelines coming
out soon recommend 400IU/day)
¨
Age 51 – 70: 400
IU/day
¨
Age 71 And Up:
600IU/day
The
bottom line is you should aim to incorporate more Vitamin D rich foods in your
diet, allow for moderate sun exposure as recommended, and discuss with your
doctor if you should supplement with Vitamin D.
