Hello there! Man does it feel good to be done with finals! My hard work paid off and now I am figuring out how to piece back together my broken friendships that I neglected for the last four months and attempt to enter back into the world of current events. I've heard something about an oil spill??....
Anyway, one of my favorite topics we covered recently in class was vitamins. Vitamins (and minerals) are micro nutrients for our bodies meaning we need them in far less quantities than we need macro nutrients-carbohydrates, fats, proteins and water. Vitamins are-for the most part-not made in our bodies. An exception to this are Vitamin K, Vitamin A, niacin, biotin and wonderful, wonderful vitamin D.
Vitamin D is a fat soluble vitamin that means unlike water soluble vitamins (which get peed out in high quantities) this guy gets stored in our liver. The Daily Recommended Intake (DRI) for vitamin D is about 200 IUs a day. You can find this stuff in things like fish liver, fatty fish (salmon), eggs, butter, fortified milk and margarine. Pretty much everyone knows you can get vitamin D from the sun, well acutally you make vitamin D from UV light which triggers a series of reactions below the skin and Vitamin D is synthesized. We need vitamin D to help maintain calcium levels in our bodies and also to absorb calcium. What some people don't know about vitamin D is that is has also been investigated lately-with some strong scientific evidence, I may add-that says vitamin D may also prevent some types of cancer.
Now there are a few different theories on how vitamin D actually does this (and I quite honestly don't fully understand all of them) but it does appear to play a role in cancer prevention. One theory indicates that a hormone called calcitriol (the active form of vitamin D) gets produced by macrophages. A quick immunology note here-macrophages are the "pac-mans" of our immune system which eat up all the bad guys in our bodies. Since macrophages produce calcitriol, it got some attention. It looks like vitamin D might kick our immune system into high gear and also inhibit production of those nasty inflammatory agents which have been known to cause cancer. I'm oversimplifying all this, of course, but I should mention there is some astounding evidence-and lots of it-to support this notion. Well I had better correct myself, perhaps not this exact theory, but the fact that vitamin D does indeed help prevent cancer. In a particularly convincing presentation, evidence suggested that higher levels of vitamin D were effective in preventing colorectal, renal and breast cancer-especially breast cancer. The studies which were presented showed that the higher a person's level of serum calcium was, the lower their risk for cancer. Even more interesting was a series of studies which showed that high serum levels also actually helped cancer patients remain cancer free for longer. The best results were for those that had high levels of calcium AND vitamin D. The studies also showed that in all cases where patients had cancer and did not remain cancer free, vitamin D levels were low.
Vitamin D has also been reported to have a role in regulating blood pressure and preventing autoimmune disorders (Crohn's, MS, Type 1 diabetes). Now I know it seems pretty crazy that with the DRI being just 200 IUs that you could reap all these amazing benefits. That is because at these levels, you probably will not. The fact is, the current DRI is way too low. An article I read at the hospital recently-which was taken down before I could get the citation information for it so you will just have to take my word for this-said vitamin D was actually the vitamin found to be the most inadequate in people. They attribute this in part to the increased use of sunscreen but most people in the nutrition field agree, vitamin D requirements need some updating.
As I mentioned earlier, fat soluble vitamins get stored, which makes them potentially toxic. Vitamin D has been said to be highly toxic BUT that claim has come under quite a bit of scrutiny as well. It's beginning to look like it may not be as toxic as we thought and the fact that it can be stored can work to the benefit of those choosing to supplement since it can be stored for a week you can take a week's worth in a day. A fellow student does this with the oral supplement drops and claims this works for her, which doesn't necessarily mean it will work for everyone. An RD in my class says she recommends about 75 IU/per kg/per day. To give you an idea of how much that is, for my body weight (which will remain anonymous-sort of) that would be 3,750 IUs a day-18 times the current DRI! This may be a tad extreme, but you get the idea that the current DRI is pretty ridiculous and professionals in the field are comfortable with recommending quite a bit more than that.
How much vitamin D is safe and effective for cancer prevention will probably be in debate for awhile and I am in no way pretending to understand the complex processes behind vitamin D's obvious beneficial mechanisms, however, I will say the current DRI is entirely too low. About 15 minutes of unsuncreened sun love a day is supposed to be adequate but for those of you not living in San Diego or for some elderly folks, supplementation appears to be quite safe and possibly extremely beneficial even for those able to get daily dose from food and sun.
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