BY MICHAEL JOHNSEN
Just because it’s in print doesn’t mean it’s true. Or accurate. Or even representative of what’s really happening out there.
That’s a significant challenge with which the dietary supplement industry has historically had to contend: First, studies or meta-analyses charging that dietary supplements don’t work, and then the press picking up on those stories, said Steve Mister, president and chief executive officer of the Council for Responsible Nutrition, during the opening presentation of Drug Store News’ Pharmacy Development Series on vitamins, minerals and dietary supplements, held in New York last month.
“What happens in the mainstream press when this research gets reported to consumers often is very negative [and] drives people out of the category,” Mister said. And when he refers to the mainstream press, he’s not talking about small regional papers with a limited circulation. Mainstream press includes The Boston Globe, Mister said, referencing an article published last year by popular columnist Judy Foreman, in which she declared her “love affair” with dietary supplements was over on account of all the negative research that’s come across her desk. Other papers of record that have been critical of the industry in the past include The Wall Street Journal and The New York Times—Jane Brody, a syndicated columnist from the Times, penned a critique of the industry on April 9 that opened: “A form of substance abuse rampant in this country is rarely discussed publicly or privately. It involves abusing legally sold dietary supplements—vitamins, minerals, herbals and homeopathic remedies—all of which can be sold over the counter without prior approval for safety and effectiveness.”
“We’ve got a media problem that we’ve got to deal with,” Mister said. “And we’ve got to figure out what is the basis for that.” Are dietary supplements 21st-century snake oil concoctions, or can the papers of record in this country really be so misinformed?
The answer, Mister noted, probably is a little bit more complicated than one or the other. It starts with the fact that dietary supplements are restricted in the claims they can make—structure/function claims as opposed to disease-state claims. That’s reflected in the fine print that winds up on the bottom of dietary supplement bottles at times— supplements cannot prevent, treat, mitigate or cure a disease. Rather, they only can improve the structure or function of an organ in the body.
But even with those marketing restrictions in place, the uses of dietary supplements often are studied for the treatment of disease or compared side by side with the uses of allopathic medicines by organizations outside the industry. The National Institutes of Health recently compared the use of glucosamine and chondroitin in treating osteoarthritis with the use of prescription pain reliever Celebrex, finding that, overall, glucosamine/chon-droitin supplements were relatively ineffective com-
pared with Pfizer’s prescription cox- 2 inhibitor Celebrex or placebos.
Another recent study determined that B vitamins did not improve cognitive abilities. However, B vitamins are claimed to prevent a decline in cognitive abilities, not to make people smarter, Mister said. A properly structured study would have compared the decline in cognitive abilities in a control group with the decline in those taking vitamin B. However, in the study, neither the control group nor the test group expe-
1 What is the question being asked?
2 What is the outcome being studied?
3 When is it OK to parse the data?
4 Is there a true control group?
5 What role does the “placebo effect” play?
6 Is the right ingredient being studied?
7 Is the right dosage being studied?
8 How accurate are meta-analyses?
9 How does this study co-exist with the larger body of research?
10 How are the results being interpreted and communicated?
in part, why there are more studies of supplements employing the aforementioned model.
To help differentiate, Mister outlined 10 questions that would enable the layperson to better evaluate whether a study on dietary supplements was inherently valid or flawed.
For example, he posed, what is the question being asked? Asking if seatbelts save lives is a much different question from: “If a person is going to die in a car accident, are they more or less likely to be wearing a seatbelt at the time?” That’s especially true if the study examines accidents only in which there was a death That would necessarily skew the outcome on ascertaining whether seatbelts save lives, but would not impact the results of the second question, Mister noted.
Another question to pose, he said: Is there a true control group? From an ethical standpoint, it’d be difficult to justify withholding a nutrient from a person’s diet, especially if you’re trying to figure out if a deficiency in that particular nutrient leads to a greater risk of disease. It’s also difficult to control a
rienced any decline in cognitive ability.
“So now, in order for there to be a benefit from the supplement, we’d have to show that the B vitamins actually improved your cognitive abilities—[that test subjects] got smarter over the two years,” Mister said. But that didn’t happen. And instead of concluding that B vitamins did not improve cognitive ability, re- Council for Responsible Nutrition’s Steve Mister said studies of the effectiveness of searchers simply stated that B vitamins didn’t dietary supplements are often misleading because they don’t ask the right questions. work. And that’s what gets reported in the newspapers,” Mister added.
It’s not science that’s at fault, however. There is a place and a need for the scientific study of whether supplements work, whether supplements are safe and at what dose they are most safe and effective. The caveat is that because dietary supplements can only be marketed as something that can improve a structure of function of the body, and not as something that can cure or mitigate a disease, the study of supplements isn’t as easy as establishing definitive endpoints over a finite period of time across a substantial enough subject base—large enough to reasonably extrapolate the data across the general population, but not so large that the study becomes cost-prohibitive.
That’s the model for OTC and prescription drugs. The most appropriate study design for dietary supplements, which looks to show the improvement of health or the prevention of a disease, would necessitate defining more general questions over a much longer period of time (multiple years, if not decades) and across a much larger patient base. And that is cost-prohibitive, which might explain,
person’s particular intake of a nutrient. Take lycopene, for example. How do you tell members of a control group that they cannot consume any tomato products (even ketchup) or anything else that may contain lycopene? Or a more dramatic example—if you’re studying vitamin D, how do you tell people to refrain from taking any vitamin D?
“This is exactly what happened in the Women’s Health Initiative [a 20-year study] with calcium and vitamin D,” Mister said. Researchers refrained from telling women in the control group to eliminate their intake of vitamin D as part of their diet because of the potential health ramifications a vitamin D deficiency would generate. Consequently, the difference between the amount of vitamin D and calcium intake in the control group vs. the study group was not that great. “So when you have women [in the control group] who are supplementing [with vitamin D] at the same intake levels, you shouldn’t be surprised that you don’t have a statistically significant difference in outcome,” Mister said. “Because everyone is supplementing.”
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