A new report from the Institute of Medicine (IOM) shows that Americans take in much more vitamin D these days, and overall the intake is adequate among in the general population.
The IOM raised the recommended dietary allowance of vitamin D from the amount cited in their last report, released 13 years ago. It said that although 600 international units (IUs) of vitamin D or more each day is sufficient to maintain bone health in majority. But those aged 71 and older may need as much as 800 IUs daily, the IOM experts say. However 1997 recommendations advised 400 IUs per day for people aged 51 to 70 and 600 IUs per day for those over 70.
Dr. Steven K. Clinton, a professor in the division of medical oncology at Ohio State University, report co-author said, “The majority of Americans and Canadians do achieve these levels… 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.” Calcium in American diet is also sufficient say experts with generally accepted recommended dietary allowances of between 700 milligrams to 1,300 milligrams per day, based on a person’s age.
These updates on recommendations come from almost 1,000 studies and testimony from scientists and others. Much of the evidence confirmed the importance of calcium and vitamin D in promoting bone health. Vitamin D, that is primarily synthesized by the body through the activity of UV sunlight on the skin has benefits beyond bone health that include protection against cancer, heart disease, autoimmune diseases and diabetes. Clinton added, “What we have are intriguing other areas that warrant research… Yet the data at the moment is insufficient with regards to defining an appropriate intake. Bone health is the primary outcome.” He said dietary calcium is often enough.
The report mentioned safe levels of both nutrients. For vitamin D, the uppermost levels are 2,500 IUs per day for children aged 1 through 3; 3,000 IUs daily for children aged 4 through 8; and 4,000 IUs daily for everyone else. For calcium, these outer ranges are 2,500 milligrams per day from age 1 through 8; 3,000 milligrams daily from age 9 through 18; 2,500 milligrams daily from age 19 through 50; and 2,000 milligrams per day for all others. Excess calcium may lead to kidney stones and excess vitamin D can damage the kidneys and heart.
Dr. Sundeep Khosla, president of the American Society for Bone and Mineral Research, said that “the recommendations overall are very sound.” Dr. Michael Holick, director of the General Clinical Research Center at Boston University Medical Center however was not wholly satisfied. He believes that most people should be taking vitamin D supplements. “I think there is no downside to people increasing their vitamin D intake… I personally get 3,000 IU of vitamin D a day. I have most of my patients on 3,000 IU a day and they are all in good shape,” he said. Andrew Shao, senior vice president of scientific and regulatory affairs at the Washington, D.C.-based Council for Responsible Nutrition said, “While an increase in the recommendations for vitamin D will benefit the public overall, such a conservative increase for the nutrient lags behind the mountain of research demonstrating a need for vitamin D intake at levels possibly as high as 2,000 IU/day for adults.” Dr. Ishwarlal Jialal, a UC Davis endocrinologist whose research has linked low vitamin D levels to higher rates of pre-diabetes and diabetes, said the report was “very fair” in its assessment that the evidence showing the vitamin can help with conditions other than bone health is only preliminary.
Americans spent $1.2 billion last year on calcium supplements and $430 million on pills containing vitamin D, according to the Nutrition Business Journal.
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