Friday, July 5, 2013

A Turnaround on Vitamins

When reading about the pros and cons of dietary supplements, most people don’t think about ordinary multivitamins.  These have been recommended and taken by children and adults for years.  Anyone who does not eat the perfect diet, we are told, must take a vitamin to make up for any possible deficiency.  Long before ginseng, St. John’s wort, chondroitin and other more exotic supplements entered mainstream America, the daily multivitamin and mineral tablet (MVM) was accepted as part of a wise, preventive health regime.  More than a third of Americans spend over $5 billion, each year on ordinary multivitamins.  That cost excludes high-dose options and other combinations of vitamins and minerals.

Although people, including health professionals, tend to view MVMs as a safe, inexpensive insurance policy, NBC news republished a report earlier this week from Prevention Magazine on two “massive studies" that cast doubt on that assumption and on the wisdom of our $5 billion expenditure.

“The first, a review of 63 randomized, controlled trials (the gold standard research method) on multivitamins, published by the Agency for Healthcare Research and Quality, found that multis did nothing to prevent cancer or heart disease in most populations (the exception being developing countries where nutritional deficiencies are widespread).”  Another study from 2012 “followed 160,000 postmenopausal women for about 10 years,” and concluded:  "Multivitamins failed to prevent cancer, heart disease, and all causes of death for all women. Whether the women were healthy eaters or ate very few fruits and vegetables, the results were the same."

The same article makes other surprising observations.  A “review of eight studies found no evidence that multis reduced infections in older adults. Another study found that the vitamins didn't improve fatigue among breast cancer patients undergoing radiation therapy. And inner-city schoolchildren who took a multi did not perform any better on tests or have fewer sick days than students who didn't take one.”

A second source, the government's National Institute of Health backs up these claims with a more detailed account of those studies and others; and it goes even further, giving examples of how use of MVMs can lead to unsafe high levels of certain vitamins in specific cases.  One finding it points out is that “investigators found that use of MVMs did not reduce the risk of any chronic disease.”

Since they are dietary supplements and not regulated by the FDA, they cannot claim to cure diseases.  As I have mentioned before, it’s left up to us to find reliable information regarding their safety and effectiveness.  Since MVMs are sold by large, reputable companies, there should be little concern about their safety, per se; and fortunately, their high popularity leads to many independent studies, separating facts from assumptions and advertising.

The latest news about MVMs agrees with the federal government's 2010 Dietary Guidelines:  "nutrients should come primarily from foods...Dietary supplements…may be advantageous in specific situations to increase intake of a specific vitamin or mineral."  Surprisingly, the population that takes MVMs tends to be better educated and take better care of themselves anyway:  keeping their weight down, drinking and smoking less, exercising more and getting regular checkups.  With a few exceptions, pregnant women for example, most who take them don’t really need them.  Couldn’t a substantial chunk of that $5 billion be put to better use?

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