Jan 29, 2015New Findings A Bitter Pill For Some
A new report that says Americans are getting more than enough vitamin D and calcium has nutritionists and dietitians scratching their heads, dietary supplement manufacturers reeling, and athletes and sports medicine professionals hearing very mixed messages. The findings from the Institute of Medicine (IOM) fly in the face of recent studies that indicated most people have very large vitamin D deficits.
The report, released last week by the IOM, tripled the recommended amount of vitamin D most Americans should take every day to 600 international units (IU) from 200 IU set in 1997. However, that increase is much lower than many doctors and major medical groups have been advocating for the last few years.
Over a two-year period, the panel looked at both vitamin D and calcium intake for different age groups and found that “with few exceptions, all North Americans are receiving enough calcium and vitamin D.” Vitamin D is found in some foods but mostly produced in human skin through ultraviolet radiation. For most adults aged 19 to 50 and for men up to 71 years, 1,000 milligrams daily is considered sufficient.
Based on its recommendations, the IOM’s message is clear: Previous research on vitamin D and its effects in areas other than maintaining and improving bone health is inconclusive at best.
“The majority of Americans and Canadians do achieve these levels,” co-author Dr. Steven K. Clinton, a professor in the division of medical oncology at Ohio State University, told Business Week. “We don’t feel there is a widespread problem of inadequacy. Most people will eat enough diverse range of foods to achieve the recommended allowance.”
In addition, the report found that for most people, adding more nutrients in pill form would be useless at best and, at worst, would risk harm. Adolescent girls were the only user group whom the researchers said should increase their calcium intake levels, albeit only slightly.
The IOM is part of the National Academy of Sciences, which sets governmental nutrient levels and its findings will be reflected in changes for the percentages of recommended daily allowances of vitamin D and calcium listed on food packages, as well as the composition of school lunch menus and other federal nutrition programs.
Perhaps the strongest message from IOM is that it based the new recommendations solely on the levels needed to maintain strong bones. During its two-year review of outside studies, the group found there wasn’t enough evidence to prove recent and popular theories that low vitamin D causes chronic health problems such as heart disease, stroke, diabetes, prostate, breast and colon cancers, auto-immune diseases, infections, depression, and cognitive decline.
“We had to look at the totality of the evidence,” Patsy Brannon, a molecular nutritionist at Cornell University who served on the panel, told Science News. “For each of those other health indicators we found very limited randomized control trials … The trials they did find didn’t establish cause and effect or clarify beneficial doses for other conditions.”
This stance on vitamin D’s effectiveness in general health maintenance could have a wide-reaching impact. According the The Los Angeles Times, the panel’s findings challenge the notion that when it comes to dietary nutrients, “more is better.” This belief has inspired a multibillion dollar market for dietary supplements in the United States. Americans spent $1.2 billion last year on calcium supplements and $430 million on pills containing vitamin D, the Nutrition Business Journal reported.
Some vitamin D advocates have taken issue with the IOM’s findings. In particular, the Vitamin D Council expressed its dismay in a press release titled “Today, the Food and Nutrition Board has Failed Millions.” In the release, John Cannell, MD, Executive Director of Vitamin D Council, wrote:
“The FNB [Food and Nutrition Board] also reported that vitamin D toxicity might occur at an intake of 10,000 IU/day (250 micrograms), although they could produce no reproducible evidence that 10,000 IU/day has ever caused toxicity in humans and only one poorly conducted study indicating 20,000 IU/day may cause mild elevations in serum calcium but not clinical toxicity … Disturbingly, this IOM, FNB committee focused on bone health, just like they did 14 years ago. They ignored the thousands of studies from the last 10 years that showed higher doses of vitamin D helps: heart health, brain health, breast health, prostate health, pancreatic health, muscle health, nerve health, eye health, immune health, colon health, liver health, mood health, skin health, and especially fetal health. Tens of millions of pregnant women and their breast-feeding infants are severely vitamin D deficient, resulting in a great increase in the medieval disease, rickets. The FNB report seems to reason that if so many pregnant women have low vitamin D blood levels then it must be OK because such low levels are so common. However, such circular logic simply represents the cave man existence of most modern day pregnant women.”
Cannell concluded by stating that the attorneys for the Vitamin D Council had been directed to file a federal Freedom of Information request for the background information the IOM used to construct its platform.
Below, Cannell shares his opinions on safe recommendations for vitamin D and calcium intake.
Here, James C. Fleet, PhD, Professor of Foods and Nutrition at Purdue University, provides his take on what consumers need to know about vitamin D.
R.J. Anderson is the Online Editor at Training & Conditioning.