Gettysburg Medical News
 The Clinical View
 by P.E. Hoffsten, MD
 28 June 2006

Vitamin D – A Tricky Business

            As a general rule, our most painful lessons are the ones that we remember the best.  Now mind you, I am not advocating painful lessons but sometimes they are thrust upon us.  Mine occurred at about 8 years old.  It was Saturday afternoon and I was going to the weekly Roy Rogers cowboy movie that cost 25 cents.  I got an allowance of 50 cents a week, which was enough to get in the movie and even buy a Coca Cola.  But this particular Saturday, there was a kid that I didn’t know standing in front of the movie theater talking about his genuine Roy Rogers Cap Pistol and how neat it was.  Rather than go to the movie, I bought that cap pistol for 25 cents, truly believing it was the greatest treasure a kid could own.  It wasn’t until I got home and tried to make it work with a roll of caps that I learned the pistol didn’t work. There were some springs broken and I had been taken to the cleaners.  That is when my daddy told me, “Whenever the person telling trying to sell you something is  the one telling you how wonderful it is, watch out!”  It was a bitter lesson but I learned.

            Now we have mass media with television, newspapers, magazines and radio touting all kinds of medicines and supplements that only cost a pittance.  The idea that antioxidants are a good thing for your health makes perfect sense until you get these items home and test them.  Now multiple studies have shown that the vitamin E story, the picolinic acid story, the vitamin C story, the vitamin B-12 story and a host of other “natural” remedies just don’t work.  Vitamin E may actually be harmful in pharmacologic doses advocated and the rest of the products touted to prevent heart disease, high blood pressure, and Alzheimer’s disease have all been debunked and are a waste of the customer’s money.

            But there are certain additives in food supplements that do have very credible benefits.  Calcium supplements at a 1,000 mg. a day is definitely beneficial if it is combined with enough vitamin D.  For women that are already osteoporotic, additional medications yet may be required; however the vitamin D and calcium are necessary if the osteoporosis medicines are going to work.  But what is the right dose of vitamin D?

            Recently a blood test to determine what a person’s vitamin D level has become available.  The test has been standardized and confirmed as reliable.  As part of the Women’s Health Initiative (WHI), vitamin D was assayed in a number of women.  It was found that over 1/3 of women over age 50 were vitamin D deficient.  They weren’t so bad off that they actually had rickets but they did have problems with osteoporosis.  A second problem that wasn’t really recognized until more recently is a tendency to have falls and weakness.  It turns out that vitamin D in adequate doses is a protector of muscle strength and also seems to contribute to prevention of falls.  One of the consequences of vitamin D deficiency is muscle weakness.  When vitamin D was supplemented to get the value up to the normal range, it was shown that there was a 22% decreased incidence of falls and a decreased incidence of broken hips in the elderly women that were tested.

            What is that right dose of vitamin D?  Years ago, the Food and Drug Administration set the adult minimal daily requirement for vitamin D at 400 IU (international units). This is the amount in a standard vitamin pill.  But it turns out that as women age and our population drinks less and less milk, the vitamin D requirements are not even met at 400 IU per day.  In fact, the real vitamin D minimal daily requirement is 800 to 1000 units per day.  This is the amount that it took to correct the vitamin D deficiency in those 1500 people who were tested in the Women’s Health Initiative. Vitamin D supplement costs about 20 cents per day and is available over-the-counter at your local pharmacies.  Now mind you, I have no financial interest in any pharmacy anywhere and whether or not you buy this is a no financial consequence to me.  So my daddy’s advice doesn’t really apply here.

            What about the other side of the coin, is there such a thing as too much vitamin D?  The answer is yes and that is the tricky part.  Too much vitamin D leads to over absorption of the calcium from your diet and leads to a high blood calcium and kidney stones.  The potential for problems here is compounded by the fact that vitamin D is a fat-soluble vitamin.  This means that there is no way to get rid of it if you eat too much vitamin D.  Water soluble vitamins such as vitamin B and vitamin C will simply be urinated out if you take too much of them. If you get too much vitamin D you have to let this be used up with time.   Over supplementation can be actually poisonous.  Thus more than a 1000 units per day of vitamin D is not recommended.  Even if a person has had kidney stones, a vitamin D supplement may be an important factor in maintaining long-term bone health. This can be discussed with your private healthcare provider as some kidney-stone formers should not take extra vitamin D and some should.

            With the changes in the American diet, a vitamin D supplement to 800 units per day is a warranted step.  Today, adult women drink very little milk and without a supplement they are intrinsically vitamin D and calcium deficient.  Those that smoke cigarettes have decreased effectiveness of whatever vitamin D they have.  Cigarette smokers will need to have special considerations to get the right amount.  At this time, it appears that the standard drink for lunch and many times at supper is soda pop instead of milk.  I can see a tidal-wave epidemic of bone disease coming in our younger generation raised without enough milk.  Speaking of painful lessons, talk to anyone who has had a broken hip!!