Friday, April 9, 2010
In the Reader’s Digest April 2010 issue an article appeared which implied that vitamins are a scam. (The Vitamin Scam). I have reprinted a response to that article from Dr. Stephen G. Chaney
Steve Chaney PhD Dr. Chaney holds a B.S. in Chemistry from Duke University and a Ph.D. in Biochemistry from UCLA.
Currently he’s a professor in the Department of Biochemistry, Biophysics and the Department of Nutrition at the University of North Carolina where he teaches first year medical students and has headed an active cancer research program for 30 years.
Dr. Chaney has published over 95 papers in peer reviewed scientific journals, plus 12 reviews and two chapters on nutrition for one of the leading biochemistry textbooks for medical students today. He’s also been named “Teacher of the Year” several times by the first year medical students and currently holds a Medical Alumni Distinguished Teaching Professorship.
Lots of you have asked me to comment on the recent Reader's Digest article called "The Vitamin Scam". If you believed that article you'd think that, except for vitamin D, all supplements were worthless - and they might even kill you.
The sad thing is that I've written about this many times before...yet the myths keep resurfacing. It's sort of like "Whack a Mole". You whack one and another pops up somewhere else!
But let me start at the beginning: The author is a journalist - not a dietitian, a scientist or a doctor! And the role of journalists is to sell magazines, papers or TV ads. The more controversial the article the better. If it draws attention, it sells.
Some critics have said that journalists "never let the truth get in the way of a good story". But that is, perhaps, not entirely fair. It's just that journalists seldom have the time or inclination to write about the subtleties of the science or point out that there are two sides to the story.
So let me make a few comments about each of the so-called myths that were "exposed" by the Reader’s Digest article.
Myth #1: A multivitamin can make up for a bad diet:
The author quotes one study that suggests that multivitamin use did not decrease the risk of cancer, heart disease or stroke. There are several other studies that have come to the opposite conclusion, but the author failed to mention those. However, none of the studies are definitive by themselves, so I think that it is fair to say that the jury is still out on this one.
I also think that it is asking a lot of a multivitamin tablet to believe that it could significantly reduce the risk of disease by itself. For example, in the Landmark study the multivitamin user group had the same or higher risk of disease than the non-supplement user group. It was only the Shaklee group, who were taking a more comprehensive approach to supplementation, that had a significantly decreased incidence of heart disease, stroke and diabetes.
Myth #2: Vitamin C is a cold fighter.
The author says that vitamin C is ineffective in preventing the common cold, but does decrease the severity of the common cold. That is actually correct, but the author worded the findings in such a negative light that you might think "Why bother?"
Vitamin C is actually often fairly effective at decreasing the symptoms of the common cold. If the cold symptoms are mild enough that you hardly know you have it, that's good enough for me.
Myth #3: Vitamin pills can prevent heart disease:
The author quoted several studies in concluding that vitamin E and B vitamins were ineffective at decreasing the risk of heart disease. But the bottom line is that supplementation makes little or no difference in cardiovascular disease or deaths if you are at low risk of heart disease – but makes a significant difference if you are at high risk.
I'm not sure that we really needed a lot of high powered clinical studies to prove that. It's just common sense! By the way, are you really sure that you are at low risk of heart disease? The first symptom is often sudden death!
Myth #4: Vitamin pills can protect against cancer:
Again the author would have you believe that supplements were worthless in reducing cancer risk. Once again supplementation had little benefit in women at low risk of breast cancer, but made a big difference in women at high risk.
Myth #5: Hey, It Can't Hurt:
Here the author dredges up those old reports that claim that vitamin E, beta-carotene or folic acid might even do more harm than good.
I've covered this topic in some past articles like"What Can We Believe About Vitamin E?", "Folic Acid: Friend Or Foe?" and "Folic Acid Recommendations – Who Decides?"
There are several take home points here:
1. Most of those reports were single studies and were outweighed by many other studies showing no detrimental effects of those supplements.
2. Even if we take the supposed risks at face value, they are far outweighed by the other beneficial effects of those supplements.
3. Finally, if there are any detrimental effects they were probably due to use of high purity individual nutrients such as alpha-tocopherol alone, beta-carotene alone or folic acid alone.
In theory that can be a problem because they could interfere with the absorption of related nutrients like gamma-tocopherol or alpha-carotene - which have health benefits of their own.
Those risks would not apply to supplements that contained all of the vitamin E family, all of the carotenoids or all of the B vitamins in balance.