Ending the multivitamin debate: Why taking one may actually save your life

Does the story adequately discuss the costs of the intervention?

Not Satisfactory

Although the article warns consumers away from “cheaper” products, it fails to disclose the costs of the suggested supplements. A back of the envelope calculation and a visit to a couple of national brand websites suggest the cost can run to $50 to $100 a month or more.

Does the story adequately quantify the benefits of the treatment/test/product/procedure?

Not Satisfactory

The story includes claims of a number of benefits that are based mainly on the findings of the Physicians Health Study II (PHS II), a multivitamin supplement trial that involved middle-aged men. There are a number of problems with the way the story describes these results:

• The story claims that 68,000 cancers a year could be prevented with daily supplement use, and that multivitamins “lowered cancer risk by 27 percent among men with a history of cancer and by 8 percent among men with no history of the disease.” The story doesn’t present these benefits in terms of absolute risk reduction, which are more meaningful. The original study  notes that there were 1.3 fewer cancer cases annually for every 1,000 men taking supplements (17.0 vs. 18.3 cases per 1000 person-years in the multivitamin group compared with the control group.)
• The story claims that there’s “there’s no reason to assume this [cancer benefit] doesn’t apply to women as well.” In fact, there’s very good reason to believe this. Other multivitamin studies that have enrolled women found no such cancer benefit. Extrapolating this benefit to women is totally unjustified and misleading.
• According to the headline, “One [multivitamin] may actually save your life.” But the PHS II found no benefit on cancer-related deaths or total deaths in the study. There was a very small reduction in the number of cancer diagnoses (not deaths) among men who took the supplements in PHS II.
• The story claims dosages of 2,500 percent of your daily value “is going to give you more of what you actually need to feel good.” The PHS II, however, used a low-dose supplement that contained around 100% of daily values — the “typical” type of vitamin that the story derides as inferior.

Does the story adequately explain/quantify the harms of the intervention?

Not Satisfactory

The article is  dismissive about reports of any potential harms of supplementation in otherwise healthy people, except to note that when people buy supplements,  they would do well to “avoid toxic fillers” consisting of “cheap additives.” In other words, no worries if you buy the expensive brands. In fact, there are studies describing harmful effects of supplements, particularly doses that are many times the recommended daily requirement suggested by ethical nutritionists and scientific organizations.  The story also suggests that the consumer “look for” specific formulations of vitamins, including beta carotene — a supplement which is known to increase cancer risk among smokers in high quality studies.

Does the story seem to grasp the quality of the evidence?

Not Satisfactory

The story goes the extra mile to describe the possible benefits of supplements, and to discuss the value of one of the studies as randomized and controlled. But it does not say a word about the limitations of the analyses cited in the article, or balance the piece with data from other high-quality studies. After systematically reviewing all available trials of reasonably good quality on vitamin supplementation, a team of experts from the US Preventive Services Task Force concluded that “current evidence is insufficient to assess the balance of benefits and harms of multivitamins for the prevention of cardiovascular disease or cancer.” This story badly needed this perspective.

Does the story commit disease-mongering?

Not Satisfactory

This story hypes the benefits of vitamins for just about everything. To read this article is to believe that most of us (actually the article says “everyone”) had better run right to the vitamin supplement aisle or have only ourselves to blame for failing to “thrive,” as well as for cancer, heart disease, dementia and other diseases. There are indeed people who have actual nutritional deficiencies, owing to illness and poverty, for example. But to suggest that virtually everyone is in urgent need of supplements is over the top.

Does the story use independent sources and identify conflicts of interest?

Not Satisfactory

The story is essentially one doctor’s pitch for consumers to buy her personalized line of supplements. We address the story’s many ethical challenges in this blog post.

Does the story compare the new approach with existing alternatives?

Not Satisfactory

The story never mentions eating fresh, healthier foods or other lifestyle modifications as alternatives to supplements in preventing disease (e.g. exercise, weight loss, or cancer screening). Further, the story inexplicably dismisses generic low-dose vitamins as an inadequate method of attaining health benefits. In fact, the best evidence available favors these low-dose vitamins — not the high doses favored by the author.

Does the story establish the true novelty of the approach?

Not Satisfactory

The headline and article suggest that the debate about the value of supplements is now over, and that the information cited in the piece is all new and previously unreported. Neither is the case. The supposedly “new” study that the story cites as appearing in the January 2015 edition of the journal Postgraduate Medicine was actually published in JAMA in October, 2012. The Postgraduate Medicine article is merely a review of that and other studies. The story doesn’t acknowledge the existence of more recent and comprehensive analyses of the evidence on vitamin supplements.