Vitamin D - Gotta Have It

I am planning to write a post on a supplement every week or two.  I'm actually not a huge fan of large scale supplementation, but I do think there are a few things that are helpful and should be taken, particularly in certain situations.  I also think there are a few that should definitely not be taken, and I'm equally excited to write about those.

The first on the list is vitamin D, which might be my favorite supplement.  It's a close fight between Vitamin D and fish oil, but I think I have to give vitamin D the edge.  The funny thing about Vitamin D is that it technically isn't - or shouldn't be - a supplement.  We actually produce vitamin D - vitamin D3, cholecalciferol - in our skin.  The precursor 7-dehydrocholesterol reacts with ultraviolet light - specifically UVB light - to form vitamin D (for the biochemists among us, there is a step in between, as precholecalciferol is formed first) (1).  Basically, we produce vitamin D from sunlight.

Now, step back for a moment and think about how much time you actually spend in the sun on the average day.  This can definitely vary a lot depending on where you live and what you do.  I live in Ithaca at the moment.  During the winter I spend literally as little time as is possible outside in the sun.  In the summer, I might play tennis or something outside for an hour or two, but on the average day, that's about it.  If you combine the demands of work that we all face, with the usual tendency to spend leisure time indoors (reading, watching TV, etc), the truth is that we don't actually get much sunlight.  That's not even accounting for the fact that we all wear clothes!  Barring the occasional trip to the beach, we get a small amount of sun on a small amount of skin for a small handful of minutes.  The result?  We don't get much vitamin D.  People with darker skin are even more likely to be deficient, as the skin pigmentation can block some of the UVB light required for vitamin D production.

Now, I'm not necessarily saying this is a bad thing.  There is an undeniable link between sun exposure, sunburns, and skin cancer.  But, it does mean that we're probably not getting as much Vitamin D as we should be.

To make matters worse, depending on where you live, even if you get full body sunlight for hours, it may not be of significant intensity to cause vitamin D to be produced (2).  In temperate regions, the sun is only regularly strong enough to cause vitamin D production in the summer.  Another unfortunate fact is that there are not really good dietary source of vitamin D, with certain types of fatty fish being the best sources.  Don't be fooled by thinking that your vitamin D fortified milk will be enough to get you buy.  It, with the vitamin D you get from other dietary sources, will be enough to keep you from getting the rickets, but it won't be enough to help you get all of the health benefits that optimal vitamin D levels will.  Unfortunately, the government's guidelines for minimum vitamin D intake seem to be enough to keep the rickets at bay, but they aren't enough to get you the help benefits of more adequate vitamin D levels.

So why should we care?  Well, the vitamin D Council is the authority on the health problems associated with low vitamin D and the health benefits related to its supplementation, and they have linked low vitamin D to a number of issues, including cancer, cardiovascular disease, diabetes (and other endocrine diseases), musculoskeletal conditions, and neurological conditions.  Remember that list of America's biggest killers this post?  This list looks remarkably similar.  I am by no means suggesting that vitamin D will cure all of these ailments, but it does seem to have a beneficial effect on these conditions.  I will leave you to explore the Council's website to research the conditions you are interested in.  Also, take a look at this chart provided by Grassroots Health, another group of scientists concerned with vitamin D.

Obivously, the last thing we need to discuss is how to deal with our potential vitamin D deficiency, and the answer, of course, is supplementation.  The Vitamin D Council suggests "For proper functioning, a healthy human body utilizes around 3,000 to 5,000 IU of vitamin D per day."  They later suggest that, in the absence of proper sun exposure, healthy adults and adolescents should take at least 5,000 IU per day.  There are also guidelines for other age groups.  Be forewarned: the US Government's upperal tolerable limit is listed as 4,000 IU per day.  The amount of vitamin D supplementation a person requires can be quite individual.  Some people may achieve optimal levels with only 1 or 2 thousand IUs per day, while others may require more.  The only way to tell is with blood tests.

Personally, I take vitamin D3 in 1,000 IU caplets produced by The Vitamin Shoppe.  If you choose to supplement vitamin D, you need to be sure to take an oil based cap, which will be an oily yellow color.  I choose to take The Vitamin Shoppe brand, due to a blog post I read by Dr. William Davis on his Track Your Plaque blog.  He is a cardiologist, and he considers one of the strongest coronary plaque fighting weapons he has in his arsenal to be Vitamin D.  In this post, Dr. Davis points out that not all supplements are created equal.  Some are simply not of high quality.  However, he has had success with The Vitamin Shoppe vitamin D brand, so that is what I choose to supplement with.  Also, if you choose to supplement, you need to keep in mind that what you're looking for is Vitamin D3, not D2; that won't get you anywhere.




Disclaimer: I am not a medical professional, nor am I in a position to give fitness, supplement, or nutrition advice.  The ideas presented within this website are simply the way I choose to live, and I am not making suggestions for others.