03/28/2008 02:48 am ET Updated Nov 17, 2011

Vitamin D: If You Can't Get It From Sun, Take The Pill

Vitamin D deficiency is probably the most frequent vitamin deficiency in America. I am writing this article to encourage you to go to the health food store and start taking 1000 International Units (IU) of Vitamin D everyday.

It is estimated that anywhere from 30 to 100% of Americans, depending upon their age and community living environments, are deficient in Vitamin D.

Studies have shown that more than 50,000 post-menopausal women taking medication for osteoporosis have sub-optimal levels of Vitamin D. 48% of white, pre-adolescent girls in a study in Maine had Vitamin D deficiency, and 32% of healthy students, physicians in residence, in a Boston Hospital, were found to be Vitamin D deficient, despite drinking milk and taking a multiple vitamin and eating salmon at least once a week.

In all, it is estimated that one billion people worldwide have Vitamin D deficiency or insufficiency.

We primarily get our Vitamin D from exposure of our skin to sunlight. Given our modern lifestyles of indoor or in-car living, and the continuous use of sun blocking creams (which block Vitamin D manufacture), most of us are getting very little Vitamin D absorption from sunlight on our skin. The little bit that we get from fortified milk and the fatty fishes does not provide us nearly what we need.

So how do we know if we have enough Vitamin D? The best way is to go to your personal physician and ask him or her to draw a 25-hydroxy Vitamin D blood test on you. This will tell you approximately what dose you need to get yourself into the normal range.

Very deficient people will need a prescription-strength Vitamin D on average for 8 weeks in order to bring them up to the normal range. Then it is simple to maintain your levels with 1,000 IU of Vitamin D which you can get at any health food store.

In the absence of getting a blood test, you can just start yourself on 1,000 IU of Vitamin D everyday.

Vitamin D deficiency has been shown to play a role in every major disease that we see in our country. This includes 17 varieties of cancer, heart disease, high blood pressure, stroke, autoimmune disease, diabetes, osteoporosis, chronic pain and periodontal disease. One study has shown that women in the lowest quartile of Vitamin D have five times the incidence of cancer compared to women in the highest quartile. 600,000 cases of breast and colo-rectal cancer could be prevented each year by adequate intake of Vitamin D, according to Cedric Garland DrPH. People deficient in Vitamin D have been found to get influenza in winter more frequently than those with normal Vitamin D levels. Vitamin D deficiency is now, most recently, being linked with autism.

If you live north of 37 degrees latitude (approximately a line drawn horizontally connecting Norfolk, Virginia to San Francisco, California) sunlight is not sufficient to create Vitamin D in your skin in the winter months, even if you are sitting in the sun in a bathing suit on a warm January day! However, given our indoor lifestyle and extreme use of sun blocking agents, living in the south is not even a guarantee that Vitamin D deficiency won't occur. A study that was conducted in Miami, Florida showed that approximately 40% of 212 adults were deficient in Vitamin D in the winter.

The normal range for the blood test for Vitamin D is currently being actively discussed in the medical literature. It appears that a minimum of 30 nanograms per milliliter, (that's ng/mL), of 25 hydroxy Vitamin D is necessary. Complementary and alternative physicians often end to get their patient's blood levels over 50 ng/mL. This is especially true when treating patients with chronic diseases, including cancer, diabetes and osteoporosis.

In my own practice in Southern California, because the majority of my patients are very busy executives, I find an approximate 80-90% insufficiency of Vitamin D. That is, the patient's blood levels are below 30 ng/mL.

In summary, Vitamin D deficiency is extremely common and affects almost all chronic diseases of the modern world. Please start yourself on 1000 IU of Vitamin D per day and discuss this with your physician. Even better get the blood test and see exactly what your dose should be!

Here are some websites where you can read more about Vitamin D deficiency: