Apr 5, 2013 3 min read

WEST PALM BEACH, Fla. – Changes in recommended calcium and vitamin D intake happen so often that it becomes confusing for doctor and patient alike.

One minute calcium and vitamin D are the darlings of bone health and cancer prevention; the next minute they are pushed off the pedestal either to be replaced with a newer and better supplement, or worse, because a new study was unable to demonstrate absolutely their alleged benefits in certain populations. Interpretation: Calcium and vitamin D are no good and should be tossed aside.

I was trying to remember when vitamin D became a craze. I am pretty sure it started with Dr. Oz for most of the population. For me it was Dr. John Kinney, a local dermatologist, who years ago touted the innumerable benefits of vitamin D3. Kinney was prophetic in his support of this fat-soluble vitamin as a source of antioxidants, beneficial for the skin, bones, and heart.

He also explained to me the myth of vitamin D – that Floridians need not worry about vitamin D because we are all exposed to the sun enough to guarantee adequate amounts of it in our bodies.

The reality is that despite living in Florida, few Floridians have adequate vitamin D levels. After that conversation, I did an experiment and measured the vitamin D levels of my next 100 patients. All but one were deficient.

I called to ask Dr. Kinney for an explanation. He stated that there were a few reasons: First, most people wear sunscreen, which interferes with absorption. Second, we limit our sun exposure out of fear of skin cancer and wrinkles. And third, as we age, even if we are exposed to vitamin D, the ability of our skin to convert it into the active form of vitamin D diminishes.

Dr. Kinney also advised me that it is virtually impossible to overdose on vitamin D, even though it is a fat-soluble vitamin and can remain in fat stores. The range of normal for vitamin D is huge: from 30-100. The lowest D level I have encountered in a patient was 4 and the highest was 114. The patient with 4 was pale as a ghost and the patient with 114 was a supplement junkie who believed that more is better with just about everything.

Although controversy still remains about vitamin D, there is a general consensus that most Americans do not consume enough, probably because the natural sources of vitamin D, such as cod liver oil, are not popular snack items. Milk and other dairy products are vitamin D fortified, but the amount per serving is insufficient to get blood levels in a solid range.

Regardless of how strongly you feel about vitamin D supplementation, most Americans should be taking it. Deciding between 400 IU, 800 IU, 1,000 IU, 2,000 IU or more should be determined with your physician.

The bottom line? Vitamin D is beneficial for men and women. It strengthens the heart, the bones and might even play a role in colon-cancer prevention. Calcium supplementation does not seem to follow suit. However, most of the negative outcomes related to calcium are limited to men, not women.

At this point, I resort to my fall-back position – everything in moderation. Some calcium supplementation is a good idea, especially in patients who are not consuming calcium-containing foods. But more is not better.

It won’t be long before another set of studies sheds new light on this very same question.

Dr. Melanie Bone is a cancer survivor and gynecologist .