'Irresponsible,' 'biased' and 'unfounded' are a few industry responses to a conference report on multivitamin/mineral supplements put out by a National Institutes of Health panel in the US.
The panel assessed 355,000 peer-reviewed nutrient studies published over the past four decades and concluded that "more rigorous scientific research is needed before strong recommendations can be made regarding multivitamin/mineral use to prevent chronic disease."
The report acknowledged the biological effects of nutrients on chronic disease states, including antioxidation, regulation of methylation, inhibitory effects on inflammation and angiogenesis. It accepted that a nationwide healthy diet is a pipe dream, noting that only four per cent of individuals older than 51 meet the adequate intake level of vitamin D.
It made three easy recommendations regarding certain specific supplements: folic acid for women of childbearing age, calcium and vitamin D to protect bones of postmenopausal women, and antioxidants and zinc to slow the progression of macular degeneration.
Besides an efficacy report, the panel also took the opportunity to call for expanded oversight of supplements, in particular with adverse events and quality production.
"We got creamed," stated Loren Israelsen, president of the LDI Group consultancy and co-author of the 1994 Dietary Supplements Health and Education Act. "'Vitamins: safe?' That's the message that will guide our government over the next five years. We in the industry see 'unregulated' and say 'What? We have this complicated law — DSHEA — and companies have to go through all these hoops.' And we see now that 'unregulated' is code for 'The government does not pre-approve.'"
The most inflammatory remark came from panel chairman J Michael McGinnis, MD, a senior scholar with the Institute of Medicine of the National Academy of Sciences. "Half of American adults are taking MVMs, and the bottom line is we don't know for sure that they're benefiting from them. In fact, we're concerned that some people may be getting too much of certain nutrients."
This triggered a firestorm of criticism regarding the perceived safety of supplements.
"Over half of all Americans take vitamins every day. One cannot help but ask, 'Where are the bodies?'" said Andrew Saul, assistant editor of the Journal of Orthomolecular Medicine. "The NIH panel ignored pharmaceutical drug dangers, while concentrating on unfounded concerns over your daily multivitamins. This indicates bias."
Saul noted that, in 2003, the American Association of Poison Control Centers noted zero vitamin deaths, squared against 59 deaths from aspirin alone.
"In decades of people taking a wide variety of dietary supplements, few adverse effects have been noted, and zero deaths as a result of the dietary supplements," said Michael Janson, MD, panelist of the Vitamin Safety Review Panel, which is not affiliated with the NIH panel. "There is far more risk to public health from people stopping their vitamin supplements than from people taking them."
The National Nutritional Foods Association objected to the panel's remarks that the Food and Drug Administration is not authorised to patrol the supplements industry.
"While it certainly may be true that the agency that regulates dietary supplements is both underfunded and understaffed, it is not powerless to enforce the law," noted an NNFA release. "Among the powers granted by the DSHEA of 1994, the FDA has the authority to seize products determined to present an unreasonable or significant risk of injury or illness or an imminent hazard to the public health. Additionally, DSHEA authorised the FDA to establish good manufacturing practices for dietary supplements."
The panel expressed safety concerns with some multivitamins that contain many multiples of the recommended daily amount — seemingly neglecting to consider that RDA levels are set to prevent deficiency diseases, not to help people achieve optimum health, which requires larger doses.
The report also referenced several studies as if their flaws had never been uncovered.
"The panel's caution that beta-carotene increases smokers' lung cancer is inappropriate because more complete data shows that the true risk to smokers was due to low total antioxidant intake," said nutritionist Neil E Levin.
One panelist noted that too much niacin, prescribed to control cholesterol, can damage the liver — but the amounts seen to potentially cause liver damage, about 3,000mg, are vastly higher than the 50mg routinely found in multivitamins.
To be sure, the report noted no trials that assessed multivitamin products on the market. Instead, clinical trials have thus far used combinations of supplements — which overall show mortality rates either lower or the same.