Multivitamin Misinformation
Monday, February 16
Once again, we have headlines like this:
Disappointing Report on Multivitamins
Be Wary of Grand Health Claims for Multivitamins
Vitamin Supplements are no Substitute for Nutrients in Food
Multivitamins Not Found to Reduce Risks
Study: Taking Vitamins Show No Benefit to Health
As usual, the mainstream media got it wrong.
Let's drill down, and see what the multivitamin study, published in the Annals of Internal Medicine, really says, and why the press conclusions are unwarranted.
The study followed over 160,000 women as part of the Women's Health Initiative (WHI). First, let's get some perspective on the WHI.
Remember the WHI study on (synthetic) estrogen? In 1998, it resulted in a premature and unwarranted conclusion that post-menopausal hormone replacement therapy was harmful to women, causing a dramatic increase in heart disease risk. As a result, millions of women went cold-turkey on their hormone replacement and unnecessarily suffered precipitous withdrawal.
Later, when the study data were re-analyzed, it turned out that women who began hormone therapy at the time of menopause, rather than in their mid-60's, actually had LOWER risk of heart disease. But that was too late for the millions of women who were misled by the study.
Later on, the WHI yielded the meaningless conclusion that restricting dietary fat had NO impact on women's health. Unfortunately, no one had thought to control for the TYPE of fat, or bothered to check whether fat was replaced with refined carbs and sugar in women opting for low-fat diets.
Finally, another arm of the WHI study showed that calcium plus vitamin D demonstrated scant benefits in forestalling osteoporosis and fractures. But, oops, the amount of vitamin D used in the study, 400 International Units, was trivial, and so, the research was irrelevant.
Keep in mind, it's your taxpayer dollars that have funded WHI, to the tune of hundreds of millions of dollars. This bodes poorly for the new Obama stimulus plan which includes billions for health care research--if we keep asking the wrong questions, will we ever get meaningful answers?
Now, the same questionable WHI weighs in on the value of multivitamins, and the press takes the bait--hook, line and sinker.
The multivitamin study was only eight years in duration, and looked at outcomes for heart disease and cancer. It's commonly acknowledged that these diseases take decades to evolve, so studying one variable over a short period of time could miss a long term impact.
Additionally--astonishingly--the WHI study relied on questionnaires (!) to verify whether women were taking "a multivitamin". Undoubtedly, some women who answered in the affirmative dutifully took their supplements every day, others sporadically, and for some, it was just wishful thinking.
There was no way to verify compliance, like by issuing and counting pills, or by checking blood levels of nutrients. It was strictly the "Honor System".
Also, what was the definition of "multivitamin?" There is no uniformity among multivitamins on the market: some offer little more protection than a bowl of Total cereal, and are laced with unwholesome additives and artificial ingredients; others are more "premium" with generous amounts of key ingredients.
For example, a check of Centrum Silver, one of America's most popular brands, and, by no means the worst of the mass-marketed multis, reveals that it contains only
55 mcg of selenium 500 IU's of Vitamin D 50 mg of magnesium 90 mg of Vitamin C 3 mg of Vitamin B6
In fact, what the press headlines didn't reveal was that among a sub-cohort of women in the study who claimed to take a beefier version of a multi--a so-called "stress multi" containing higher doses of several B vitamins and an extra jolt of vitamin C--there was a 25% reduced risk of heart attack!
So, in short, hundreds of millions of dollars later, we are left with misleading conclusions from an ill-conceived study that sheds little light on the health benefits attained by the millions of Americans who take a balanced portfolio of high-quality vitamins. And the press, regrettably, has again breached its responsibility to accurately report and interpret the facts to the U.S. public.
|