Vitamin D daily consumption recommendations could double when the U.S. Institute of Medicine makes its announcement at the National Press Club in Washington, D.C., on Tuesday, Nov. 30.
Current intake levels are 200 IU/day for those up to age 50, 400 IU/day for those ages 51 to 70, and 600 IU/day for those older than age 70.
While many in the industry say the state of the scientific research points to appropriate daily intake levels of 2,000 IU/day, the final decision could be only 1,000 IU/day – or less.
“My guess is that the IOM will be setting vitamin D RDAs of 400 IU/day for children and either 800 or 1,000 IU/day for adults,” said David A. Mark, Ph.D., of dmark consulting in Boston. “Given that foods supply only 150 IU/day, there may be room for expanded fortification.”
Also at play are upper intake safety thresholds, which currently stand at 2,000 IU/day. A 2009 report from the Agency for Healthcare Research and Quality(AHRQ) did not offer new information on safety, making downward changes unlikely, and potentially raised to 2,500 IU/day, said Mark.
Even with these conservative recommendations, it would still amount to a doubling of current recommendations. As the mainstream media announces this, consumer interest in vitamin D – already at high levels despite chronic deficiencies among all population groups studied – can be expected to tick upwards again.
Also, it is believed that to increase levels by too great an amount – whatever the research – can be too much for consumers to stomach, so they tune out altogether, according to Brian Wansink, the John Dyson Professor of Consumer Behavior at Cornell University. Wansink who on the IOM committee when it unveiled the revised Food Guide Pyramid recommendations in 2005.
The IOM review was to consider new research since it last revised vitamin D intake levels, in 1997.
“Everything we know about vitamin D we’ve learned since 1998,” said Robert Heaney, MD, a researcher and professor at Creighton University in Nebraska who sat on the IOM committee when it last unveiled vitamin D recommendations in 1997.
Specifically, the agency was looking at indicators for chronic disease risk reduction as well as other health outcomes. IOM researchers also were to incorporate, as appropriate, systematic evidence-based reviews of the literature and organize a risk assessment. Indicators for adequacy and excess were to be selected based on the strength and quality of the evidence and the demonstrated public health significance, taking into consideration sources of uncertainty in the evidence.
Very few foods naturally contain vitamin D. It’s actually a pro-hormone and not technically a vitamin – which, by definition, is essential for life but can be obtained only from the diet, whereas most vitamin D comes from sunlight. Food sources with vitamin D include salmon, tuna and mackerel and fish liver oils. Most dietary sources of vitamin D come from fortified foods and beverages, most predominantly milk and cereal. Milk usually contains 100 IU/cup.
Vitamin D sales have skyrocketed over the last decade, as research and positive media headlines have driven doctor and consumer interest in the sunshine vitamin. According to Nutrition Business Journal, sales of vitamin D supplements jumped 82% to $430 million in 2009.