The following is an excerpt from The Willner Window radio program, originally broadcast on WOR (710 AM), on February 11, 2007. The opening topic was vitamin K, and its role in bone health.
Arnie: Good afternoon everyone, this is .... Welcome to The Willner Window. For those of you who might be first-time listeners, the focus of this show is nutritional supplements–vitamins, herbs, homeopathic remedies–and their proper usage. With me this afternoon is . .
Today, we are going to talk about a nutrient that might not be getting as much of your attention as it should–vitamin K.
Maybe you've been around for awhile, and you still associate vitamin K with blood clotting. Maybe you remember something about infants being given injections of vitamin K to prevent hemorrhagic disease.
Don: Or, maybe you heard someone talking about vitamin K, but they got all caught up with talk about K1 versus K2, the natural forms, compared to K3, the synthetic form, which is called menadione, as opposed to K1 which is known as phylloquinone, different from K2 which is actually a group of compounds called menaquinones, or MK-n, not to be confused with menadione, which, actually, isn't really vitamin K but is actually provitamin K. . . and your eyes rolled to the back of your head, and you went to get a cold beer.
Dr. Podell: Yes, vitamin K can get to be a little complicated. But for you, it doesn't have to be, and, as you know, you can count on the Willner Window to cut through to the basics, helping you understand what you really need to know.
And knowing about vitamin K is important, because it is now becoming very clear that vitamin K plays a very important role in maintaining bone health, preventing and treating osteoporosis, and preventing fractures. It is also being looked at for other problems, including heart disease and cancer, but we will leave that for another time.
Arnie: How does vitamin K play so wide and important a role in this seeming wide array of health problems? The answer is that it has a role in regulation the way calcium is utilized in the body.
It is important to recognize that it is critically important to regulate the level of calcium throughout the body–in the blood and in the body's cells. Too much or too little calcium in the blood can be life-threatening. Too little calcium being deposited into the bone can be bad, and too much calcium being deposited in the artery wall can be bad.
Dr. Podell: One of the things that controls these various aspects of calcium regulation and deposition is a chemical reaction called carboxylation. Now, here is the key: A certain protein that regulates carboxylation is activated by vitamin K!
When vitamin K levels are not high enough, these carboxylation controlling proteins cannot do their job properly, and calcium is allowed to leave the bone, rather than being deposited there, and find its way into other soft tissue, such as arteries.
Arnie: So there is something of an inverse relationship between vitamin K's effect on osteoporosis and heart disease. If vitamin K does it's job properly, calcium will be kept away from places it does not belong, like artery walls, and will be put into those places where it does belong, such as bone.
Don: Now you understand, by the way, why one side effect of using Coumadin, the blood thinner, is increased risk of osteoporosis. Coumadin, or warfarin, works by blocking the activity of vitamin K in the blood clotting reaction. So when you take coumadin, you risk creating a deficiency of vitamin K.
Dr. Podell: This is not something that is just now being discovered, by the way. Vitamin K has been used as a treatment for osteoporosis in Japan since 1995.
In fact, the connection between osteoporosis and artery disease has long been known to be epidemiologically related; patients with osteoporosis have a significantly greater chance of<