The Making of a New Urban Legend
There are many urban legends in medicine that actually have no basis in fact. But once they become ingrained in medical lore, few doctors will question whether they are accurate.
Examples of what I feel are urban legends include the following: 1) the lowering of cholesterol prevents heart attacks, 2) flu shots prevent the flu, 3) vitamins and other supplements will only result in expensive urine, 4) natural progesterone does not have to be replaced after women have had a hysterectomy, and 6) blood tests should be done in a fasting state (please see my blog).
My feeling is that the creation of an urban legend requires two factors: 1) the publication of an article making a certain claim, and 2) the failure for healthcare practitioners to read the entire article instead of the abstract at the beginning.
For example, a recent article in Life Extension Magazine warned of the danger of having 25-hydroxy vitamin D levels greater than 100. The article stated that there was a 2.5 fold increase in the incidence of atrial fibrillation at these levels. This warning, of course, will be the take-home message that many doctors incorporate into their practice. However, a closer examination of the article reveals that it failed to mention exactly how many people had this side effect, nor do they mention the ages of the people in the study. This is important information because it is known that 5% of people over the age 65 develop atrial fibrillation.
It was pointed out at the end of the article that the majority of people with levels over 100 had significant hypothyroidism. This condition is a known cause of atrial fibrillation. In other words, one cannot conclude that vitamin D was the cause of the higher incidence of atrial fibrillation.
Normal vitamin D levels are stated to be between 30 and 100. My feeling is they don’t really know what a normal level of vitamin D should be. It appears that most of us have lost the ability to convert sunlight into vitamin D. Studies done in Hawaii and Costa Rica have indicated that residents there all have low vitamin D levels. In my own practice in Southern California I have never had a patient with a normal vitamin D level who was not taking vitamin D.
It has been reported that there was a time that 15 minutes of sunshine would result in 10,000 to 20,000 units of vitamin D. Before the advent of the automobile and office buildings man spent most of the daylight hours out in the sun. So the question is, how much vitamin D should really be taken to be equal to the amount that we used to produce?
Vitamin D3, as many of you know, has significant benefits. Many of these are related to the fact that it is a prohormone, rather than a vitamin. It has been said that it prevents 26 different cancers, especially breast and prostate. In high doses it prevents the flu, type II diabetes, dementia, helps with depression, and prevents and helps to eliminate osteoporosis.
Please keep in mind that it is necessary to add vitamin K when taking vitamin D3. The reason is that vitamin K prevents vitamin D from putting calcium into blood vessels and it actually takes calcium out of blood vessels and puts it into bones. My recommendation is to use about 200 mcg of MK-7, a type of vitamin K2. It will not affect clotting.
Every cell in the body has a receptor site for vitamin D. Over the years, I have routinely recommended 10 to 15,000 units per day in thousands of my patients and have never had anyone develop atrial fibrillation nor any other side effects. They all had blood levels greater than 100. Since they try to prevent preventive medicine in this country, not surprisingly, the Institute of Medicine recommends doses no greater than 400 to 600 units per day. With this dosage it eliminates every benefit except for bone health.
Please let me know if there is any interest in other examples of how urban legends effect the practice of medicine.