I'm writing to tell you how refreshing it is to hear straight talk about dietary supplements. The hemp-clouded birdbrain working the vitamin counter constantly confuses me. Worse than him are the other customers (they are always just skin and bones, too) trying to convince me to buy stuff I don't need. Why are natural food enthusiasts so deranged? From lack of protein, no doubt, but I'd like to hear your opinion.
—Daryl J.P., Mountain Home
[edited significantly for rant-removal]
Thanks for the compliment, but I have to wonder why you're in the natural foods store in the first place. You are definitely not the typical customer and I expect that your visit is not all that pleasant for the "birdbrain" either. Perhaps you're there (and I'm just guessing here) for some calming herbs, like valerian or kava-kava. Regardless, and for your own safety, I'd suggest toning it down a notch at the vitamin counter as the taste of natural laxatives can be easily hidden in a free sample of fresh carrot juice.
As far as contradictory information given out by store clerks and customers, they truly cannot be blamed. The dietary supplement industry is booming as more than half of the adults in the United States are swallowing some sort of daily nutritional enhancement. With a growth curve like that, manufacturers and promoters have significant incentive to provide the most carefully worded—but completely misleading—information to retailers and consumers. And as you know from reading this column, the moment one myth is busted, two more appear to take its place. Beyond my expertise, however, is what makes your fellow customers deranged and skeletal (though I do have an idea about the hemp).
The motivation to take vitamins, on the whole, is to stay healthy and to avoid age-related illness. To that end, the most widely consumed supplements are antioxidants (specific substances thought to protect cells from free radical damage) and multivitamins (containing any number of combinations of vitamins and minerals). Some take it further, attempting to turn around the normal aging process. These latter, idealistic types should be aware that—among antioxidants, vitamins and hormones—no single compound has ever been shown to reverse aging. The moment one is found, and for the good of the entire country, I will immediately send a bottle to Danny Bonaduce.
Outside the nutrition store, there is evidence building against even the most routine supplementation. For example, nearly all large studies of antioxidants—including, but not limited to the poster boy, beta-carotene—have determined that regular use does not prevent (or even affect your risk of) cancer or cardiovascular disease. In fact, for smokers, additional beta-carotene is shown to actually increase rates of lung cancer. One theory why antioxidants haven't met their promise may be drawn from a study in which high doses of vitamin C (another antioxidant) in mice appear to essentially shut down the manufacture of the body's natural free radical defenses.
Bad news, too, for Flintstones Chewables: Investigations of multivitamins have similarly unimpressive findings. A 2006 meta-analysis (a study of multiple, previous studies) published in the Annals of Internal Medicine concluded that there is insufficient evidence to state that a daily multivitamin/mineral provides any protection, whatsoever, against cancer or heart disease (as she is fictional, Wilma Flintstone could not be reached for comment). The authors here are specifically talking about routine supplementation; they are clearly not referring to individual nutritional needs like folic acid to prevent birth defects in pregnancy, or calcium and vitamin D to maintain bone density and prevent fractures in postmenopausal women.
In what should be the near-final word on the subject, a second Physician's Health Study (the first discovered, among many other things, that aspirin decreases risk of first heart attack) will be completed by the end of this year. This massive, 10-year undertaking has been following 14,000 male physicians to test the effect of antioxidants and multivitamins on the rates of cancer, cardiovascular disease, cognitive decline and age-related eye disorders (cataracts and macular degeneration).
Although artificial supplements may turn out to be of little use, there is still abundant evidence that a diet heavy in fruits and vegetables decreases the risk of cancer and heart disease. The obvious conclusion is that something in unprocessed food, other than simple vitamins, is of primary importance to our health. This discussion, added to my prior work, gives you and me something in common: Neither of us is making many friends at the nutrition counter. And, seeing as my picture is published along with the column, I'll be avoiding the carrot juice, too.
Dr. Ed Rabin is a chiropractor practicing at Life Chiropractic Center in Boise. Send free (or low-priced) radicals and health-related questions to firstname.lastname@example.org (on the Web at www.edrabin.com).