Just when it seemed vitamin D had secured its status as the new must-have supplement on the market, a report out today says extra dosage isn’t necessary for most consumers, and could in fact be harmful.
A panel convened by the Institute of Medicine combed through years worth of studies on vitamin D and calcium with the goal of determining what levels of each are needed to maintain optimum health, and how much, exactly, is too much. Both nutrients are essential to bone health, and in recent years studies have drawn links, especially in the case of vitamin D, to a possible role in preventing heart disease and other conditions.
The committee concluded that the majority of people are getting adequate amounts of both nutrients, and warned against taking more than the upper level intake recommendations. In the case of calcium, most adults get 800 milligrams daily, which is close enough to the recommended 1,000mg. Going above this does amount doesn’t provide any extra benefit, the researchers noted, and going over the ceiling of 2,000 to 2,500mg may have detrimental effects, such as the production of kidney stones.
The recommended level of vitamin D, meanwhile, is around 600 IU/day, with most people getting 400 IU through a combination of diet and sun exposure. That’s healthy, according to the report, and again there’s no evidence that going above that level is helpful. Going above 4,000 IU/day, in fact, could increase the risk for fractures and other complications.
None of this will sit well with the supplement industry, which has seen vitamin D balloon to a $500 million industry. Food and drink manufacturers, too, have fortified their products and frequently market them as “a good source” of both nutrients.
Retailers are heavily invested here, and that might cause them some worry. The report, however, isn’t saying that all vitamin D and calcium supplementation is bad — just that they shouldn’t take too much. There’s skepticism about the proposed benefits, but that won’t likely sway consumers who swear by these supplements. For years, reports have cast doubt on vitamin C and zinc’s effectiveness against colds, and people still continue to buy them.
The best prescription, though, is to base all of your sales on good science.
(Creative Commons photo by thegarethwiscombe)