Blinders In Place
"Here we go AGAIN…" was the only message in an e-mail a colleague sent me last week. Her words were attached to an article with this headline: "Study Finds Antioxidant Vitamins Useless"
That's right - "useless." Once again vitamin supplements are under attack. And as is so often the case, the attack involves researchers who conclude with sweeping generalizations, and news writers who emphasize the most inflammatory aspects of those generalizations. And - once again - when you see the reality hidden in the details, it completely takes the bite out of the scare headlines. This time the attack comes from the Cleveland Clinic Foundation, as reported in The Lancet. Researchers reviewed seven trials that evaluated the effectiveness of vitamin E supplements in preventing death or stroke due to cardiovascular events. An additional eight similar trials that tested supplements of beta-carotene (vitamin A) were also reviewed. The combined results showed that neither of these antioxidant supplements reduced the risk of stroke or death due to cardiovascular problems. In addition, when the columns of numbers were added up, it appeared that beta-carotene supplements actually increased the risk of death. Across the country, headline writers picked up the Associated Press coverage of The Lancet article and refined the message to tight, damaging phrases designed to catch the eye:
"Antioxidant Pills Don't Make Heart Healthier, Study Says"
"Study Says Antioxidant Vitamin Use Misguided"
"Antioxidants Rated Useless for Hearts"
Taken at face value, all three of those headlines are false.
Each of the above headlines would come much closer to the truth if they added this sub-head: "…In Cases Where Patients Are Already at High Risk."
In other words, if you're a healthy person who takes vitamin E, beta-carotene, or any other antioxidant supplement to help protect your heart, this research doesn't pertain to you at all because most of the subjects in the 15 studies already had heart disease or other conditions that would elevate their risk of cardiovascular failure. And keep in mind that this research only looked for statistics that recorded deaths or strokes associated with cardiovascular events. Finer points that would address the prevention of heart disease - such as an antioxidant's ability to help lower homocysteine, triglyceride, or C-reactive protein levels - were not examined. So then - just how misleading is a statement like, "Antioxidants Rated Useless for Hearts"? It's completely misleading.
But what about that surprising and troubling detail that beta-carotene supplements may INCREASE your risk of death?
For reasons that are not yet clear, a high intake of beta-carotene has been shown to complicate heart problems for smokers. Two of the beta-carotene trials examined in this research included subjects who were smokers (which qualified them for the study as having a risk factor for heart disease). In both trials the increased risk of death occurred mostly with smokers taking large doses of beta-carotene, and it was this set of statistics that resulted in the unconditional blanket claim that beta-carotene may increase the risk of death. So if you're a non-smoker who is not at risk of heart disease, will you be flirting with the grim reaper if you take a standard dose of beta-carotene? Of course not. But these important little details are nowhere to be found in the widely reported Associated Press article.
Also missing are specifics about the vitamin E supplements used in the studies. As HSI Panelist Allan Spreen, M.D., pointed out in the e-Alert "Deconstructing JAMA" (8/27/02), only the "mixed tocopherol" variety of vitamin E should be used. If an alpha tocopherol supplement is used, the other vitamin E fractions - beta, delta, and gamma - are decreased in value.
Was the vitamin E used in these seven studies the more effective variety of mixed tocopherol? The answer can only be: "Maybe." These were not controlled trials where uniform amounts of the same supplement were used. Subjects were simply asked to report their supplement intakes - some of them over a period of 12 years. Chances are very good that many of the 81,000 total participants were taking a less effective generic brand of alpha tocopherol vitamin E.
When I read reports like this, it's sometimes hard to tell if the researchers don't get it because they have another agenda to promote (which is most often the case), or if they don't get it because they just don't get it. In either case - as always - the loser is the consumer who receives misinformation like this, acts on it, and ends up missing out on a health benefit.
So if you should hear anyone talking about how "useless" antioxidants are in promoting heart health, you can fill them in on this reality: when the mainstream media gets hold of imperfect research, some of the most important details almost always get lost along the way. To Your Good Health, Jenny Thompson
Health Sciences Institute Sources:
"Use of Antioxidant Vitamins for the Prevention of Cardiovascular Disease: Meta-Analysis of Randomised Trials" The Lancet 2003; 361: 2017-23
"Study Finds Antioxidant Vitamins Useless" Emma Ross, Associated Press, 6/12/03, ap.org
"CRN Voices Concern Over Irresponsible Conclusions Reached by Researchers in The Lancet" The Council for Responsible Nutrition Press Release, 6/12/03, npicenter.com
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