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Supplements Headed Downstream?
6 November 2000
by Wyn Snow, Managing Editor

A noted cardiologist with a decidedly negative bias toward vitamins and herbs recently remarked that supplement-gobbling Americans have created a nation with "the most expensive urine in history." Which raises an interesting question: Are we literally flushing away our money on dietary supplements? Perhaps, according to at least three sources.

Dr. John Potter of Seattle's Fred Hutchinson Cancer Research Center, observes that 190 solid studies prove the cancer-fighting benefits of eating lots of fruits and vegetables, but "supplements have only a smattering of evidence" supporting their ability to fight cancer -- (Reported by AOL news on 4 September 2000).

Dr. Stephen Barrett, author of the Quackwatch website, says, "A few [dietary supplements, herbs and hormones] are useful, but most are promoted with false or misleading claims."

And concerning the recent trend of adding herbal supplements to foods (so-called functional foods), "Food companies are . . . misleading consumers about their health benefits," according to Bruce Silverglade, director of legal affairs for the Center for Science in the Public Interest (CSPI). "It's shameful that respected companies are selling modern-day snake oil."

Are Americans then behaving foolishly by spending upwards of $15 billion annually on dietary supplements? More and better designed research is needed to answer this question fully -- although some results are available now.

IBIDS database bursting with research

The International Bibliographic Information on Dietary Supplements (IBIDS) Database recently completed its sixth quarterly update -- and now has upwards of 400,000 unique bibliographic records about dietary supplements from 1986 to the present. IBIDS is a searchable database of published, international, scientific literature on dietary supplements, including vitamins, minerals, herbs and botanicals.

Critics of international research characterize much of it as flawed in various ways -- but solid, reliable, well-designed, peer-reviewed evidence about the health benefits of many supplements is growing. Links to several research databases are available in the links section of our website. And news about various new studies -- some of it quite positive -- appears regularly in the media. Two typical examples focus on antioxidants and the popular joint supplements glucosamine and chondroitin.

Vitamins plus antioxidants improve heart disease mortality rates

Taking a multivitamin together with an antioxidant (vitamin A, C or E) appears to reduce one's risk of dying from heart disease or stroke by approximately 15% -- according to a study reported in the July issue of the American Journal of Epidemiology that followed 1 million Americans aged 30 and older for 7 years. However, people who took only a multivitamin did not fare better than those who took no vitamins at all -- and the study showed no differences in cancer death rates between those who took supplements and those who did not.

Glucosamine and chondroitin ease osteoarthritis pain

Five million Americans now use glucosamine and chondroitin sulfate, partly because of their effectiveness in animals and partly because of the best-selling book, The Arthritis Cure -- according to an article published in The Boston Globe on 25 September 2000.

Dr. Timothy McAlindon of Boston University examined the European research on these supplements (more than three dozen studies) and concludes they are safe and do reduce osteoarthritis pain, according to his report published earlier this year in the Journal of the American Medical Association. McAlindon says, "At the moment the evidence is favoring these products,'' but added that most of the European research was sponsored by supplement manufacturers and "was not that well done. They seem to exaggerate the treatments' efficacy."

To address these concerns, the effectiveness of glucosamine and chondroitin will soon be addressed in NIH-funded research studies. A $10 million project with 1,500 patients will look at whether these two supplements reduce arthritis pain, and whether they impact the disease itself. According to Dr. Robert Karpman in Phoenix, AZ, "It seems to slow the arthritic process, but it doesn't repair the joint surface.''

Profit-making organizations often do flawed research

Supplement producers are not the only authors of flawed research -- according to an article published in The Lancet in August 2000 and reported in AOL News on 17 August 2000.

"A clinical trial should only be carried out if there is substantial uncertainty about which one of two treatments is more effective," according to Benjamin Djulbegovic of the H. Lee Moffitt Cancer Center and Research Institute at the University of South Florida. But in 136 trials of treatments for a specific blood disease, Djulbegovic and his colleagues found that trials "funded partly or only by profit making organizations" showed a strong tendency to prefer the experimental treatment over older methods (74% versus 26%), while trials "supported by governments and non-profit organizations" were more balanced (47% versus 53%).

The profit-making organizations were more likely to use inferior controls, thereby creating a bias favoring the new treatment. According to Djulbegovic, "Profit-sponsored research used inferior controls in 60 percent of cases while trials funded by non-profit organizations only used inferior controls in 21 percent of cases."

Independent research on the rise

Such flaws are an excellent argument in favor of independent, basic research performed by academicians. The National Institute of Health (NIH) is now funding four research centers focusing on botanical supplements through the Office of Dietary Supplements (ODS) and the National Center for Complementary and Alternative Medicine (NCCAM). Each center receives approximately $1.5 million per year for five years. These four research centers are:

  • The UCLA Center for Dietary Supplements Research on Botanicals, directed by Dr. David Heber, is researching yeast fermented rice, green tea extract, soy isolates, St. John's wort, and levels of bioactive compounds in several botanicals.

  • The University of Illinois at Chicago, directed by Dr. Norman Farnsworth, has established a Dietary Supplements Research Center focusing on ten herbal supplements that may benefit women's health issues, including menopause.

  • The Purdue Center for Dietary Supplement Research on Botanicals (at Purdue University), directed by Connie Weaver, PhD, will study the health effects of polyphenols (a diverse group of chemical components widely distributed in plants) -- many of which are consumed both for their nutritive value and medicinal properties. Examples include soy, grapes, green tea, and several herbs.

    The Purdue Center's proposed research is important for heart disease, cancer, osteoporosis, and cognitive decline. Purdue researchers will collaborate closely with investigators at the University of Alabama at Birmingham (UAB), directed by Stephen Barnes, PhD.

  • The University of Arizona Center at Tucson, directed by Barbara Timmermann, PhD, will focus on three botanicals (ginger, turmeric, and boswellia) widely used in Ayurvedic medicine for the treatment of inflammatory diseases. The researchers propose to identify the active constituents of these three herbs and study their pharmacological activity.

Supplements and drugs: Apples and oranges?

With new US-based supplement research expanding rapidly, a few often overlooked facts about supplements are worth noting. For instance, many of the active ingredients in supplements, when synthesized and refined, are the basis for well studied and proven over-the-counter remedies as well as prescription drugs.

Similarly, recent studies of St. John's wort were reported on in The Boston Globe, but with a critical focus on variations in standard dosage and uniformity of product quality. Almost without comment, Globe coverage noted that St. John's wort contains naturally occurring reuptake inhibitors of seratonin and dopamine, in amounts comparable to the primary psychoactive ingredient in Prozac, enough so that patients with moderate levels of depression taking the supplement would receive useful amounts without having to resort to the much more expensive drug.

For those wondering whether supplement users are flushing away money that might better be directed elsewhere, the jury is not only still out, it has yet to be really convened. A gathering volume of research is pointing toward positive results, and clinical studies done under federal sponsorship will also bear careful analysis.

In the meantime, consultation with knowledgeable care givers and an eye to verifiable supplement quality are still the best way to avoid being swept downstream on a tide of cynicism and misplaced contempt.


"Nutrition Industry Sales Reach $44.5 Billion." Nutrition Business Journal press release, 5 October 2000.

Stephen Barrett, MD. "`Dietary Supplements,' Herbs, and Hormones." Quackwatch.com, www.quackwatch.org/01QuackeryRelatedTopics/DSH/suppsherbs.html, (updated most recently 9 October 2000).

Center for Science in the Public Interest. "FDA Urged to Halt Sale of `Functional Foods' Containing Illegal Ingredients." Press release, www.cspinet.org/new/fda_functfoods.html, 18 July 2000.

Lauran Neergaard. "Dietary Supplements No Substitute" [for Food]. The Associated Press, AOL news, 4 September 2000.

Reuters. "Clinical trials break basic scientific rules." AOL news, 17 August 2000. (Reporting on Benjamin Djulbegovic et al. "The uncertainty principle and industry-sponsored research." The Lancet, August 2000, Vol. 356, Issue 9230, page 635.)

Reuters Health Information. "Vitamins Reduce Risk of Death From Heart Disease, Stroke." Vitacost.com news, www.vitacost.com/whatnew/news/aug2000/news08vit.html (Reporting on article in American Journal of Epidemiology, July 2000;152:149-162.)

Larry Tye. "Boom for joint drug prods scientific study." The Boston Globe, 25 September 2000.end-of-story


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