Vitamin D on the Loose

People are being warned about vitamin D. According to the New York Times, you should worry about getting too much. But if you read the Wall Street Journal, you might worry that you’re not getting enough. Each mainstream media outlet was reporting recommendations issued by the Institute of Medicine.

In terms of accuracy in reporting, the Times was more accurate in sounding the alarms raised in the Institute’s report, but the Journal did a better job of critically evaluating what the Institute actually said. What the report actually said was that, in their expert opinion, the official Dietary Reference Intake for vitamin D should be increased a bit because of bone health benefits. The Dietary Reference Intake for a nutrient, referred to as its DRI, is a standard for how much of the nutrient people should take each day. So basically, the Institute was recommending an increase in vitamin D.

However, what the Institute’s report emphasized was that vitamin D does not provide a benefit for anything other than bone health. “Scientific evidence indicates that calcium and vitamin D play key roles in bone health. The current evidence, however, does not support other benefits for vitamin D or calcium intake.” Of equal importance, the Institute reports that people are already getting enough calcium and vitamin, thank you very much. “[T]he committee emphasizes that, with a few exceptions, all North Americans are receiving enough calcium and vitamin D.” In other words, taking vitamin D and calcium supplements is not only unnecessary, but potentially dangerous.

The Institute’s report elicited a vigorous and critical discussion on the listserv of the Collaborative on Health and the Environment, referred to as the CHE List. The Institute’s evaluation of the science was challenged on a variety of issues. I’ll list only a few here, taken principally from the contributions of researcher Teresa Binstock and compounding pharmacist Mark Burger.

In general, the Institute’s perspective fails utterly to take into account the complex interaction of vitamin D with nutrients other than calcium. For example, the science they use takes no account of the role played by vitamin K and vitamin A. Vitamin K helps vitamin D keep calcium out of soft tissues like heart valves and arteries. Vitamin A helps regulate the receptor sites that it and vitamin D occupy along with other steroid hormones. In other words, the Institute’s approach was very much in keeping with conventional vitamin science: study them as if they were pharmaceutical magic bullets and not as one ingredient in a stew of nutrients that work together.

You’ll recall that I just said “vitamin D and other steroid hormones.” Vitamin D is functionally a hormone. Yet when I look at the people who served on the committee that wrote the Institute’s report, I see only one endocrinologist. The vast majority of the committee members are nutritionists. There is no doubt in my mind that all committee members were carefully selected to reflect the conventional, reductionist approach. I did not see, for example, anyone from the Linus Pauling Institute, where they know a little something about nutrients. In addition, the Endocrine Society, the organization for endocrinologists, has yet to weigh in on this report. Their website says they’re looking it over because they have their own evaluation going on. The Wall Street Journal reported that the Endocrine Society as well as the International Osteoporosis Foundation disagree with the Institute’s recommended blood test levels as being too low.

This brings me to what I believe is the real purpose of this report. It’s not to set standards per se but to discipline health practitioners. What the committee of nutritionists says alarms them is that practitioners test patients for vitamin D levels, find them low, and prescribe supplements. The issue here isn’t whether the practitioners know what they’re doing. The issue is that they’re not following the Party Line.

The Lords of Vitamin Standards don’t like it. They’re not kidding. They’ve got the science behind them. They’ve got the Institutions behind them. So watch your step, buddy.

The two things wrong are these. First, treating people to a standard means not treating the actual person at all. Your vitamin D needs are not the same as mine. Second, the committee says in one place that “current evidence … does not support other benefits for vitamin D or calcium intake.” But in another it says that “the data do not … provide compelling evidence.”

Does evidence have to be compelling in order for you to act on it? And compelling to whom?