Is This the Last Word On Vitamin Supplements?
The controversy has been raging for decades, at least since the late Linus Pauling suggested in the 1950s that megadoses of Vitamin C could cure not only the common cold, but a host of human illnesses and conditions.
Now a new research review attempts to answer the question regarding the effectiveness of vitamin supplements, at least regarding whether they can help prevent heart disease.
Because your primary care doctors at Cohen Medical Associates in Delray Beach, Florida, often receive questions about vitamin supplements from our patients (which we strongly encourage, by the way!), we’d like to explain these new findings to you, and also to explore the most reliable evidence on vitamin supplements.
Dietary supplements are a multibillion-dollar industry in the United States, but their benefits remain unclear. For example, three separate studies performed in 2013 and published in the journal Annals of Internal Medicine (AIM), found that the multivitamin supplements they studied worked no better than placebos at preventing cardiovascular disease, slowing memory loss, or extending lifespan.
Another example was the SELECT study, which tracked 35,000 men for over a decade to see whether vitamin E and selenium supplements could prevent prostate cancer. The study was halted in 2008 when researchers found an increase in prostate cancer among participants, which they attributed to the vitamin E supplements, and a similar increase in the development of diabetes which they said was due to the selenium supplements.
And here’s the issue with supplements: In some cases they could be dangerous. Some people who megadose with vitamin C, for example, even in the short term to fight colds, develop diarrhea. Hardly life-threatening, but definitely inconvenient. Other megadoses can have more deadly consequences. Two different studies that involved supplements with beta carotene to help prevent lung cancer found that the substance, which the body converts to vitamin A, actually increased lung cancer rates. Other studies found a similar result with vitamin E supplements, increasing lung cancer rates among smokers. Studies researching the B vitamin niacin showed an increased risk of death with use of this supplement.
The most recent review, published this month in the Journal of the American College of Cardiology (JACC), performed meta-analyses on previous studies involving cardiovascular disease and vitamin consumption. It showed no benefit in vitamin supplements in preventing cardiovascular disease. This study at the University of Toronto looked at multivitamins, C, D, beta carotene, selenium, and calcium. It found that conclusive evidence for the benefit of any supplement studied was not demonstrated, and suggested that the use of any vitamin or supplement should be weighed against the risk.
The problem with isolating vitamins from foods and expecting them to perform as they do in the diet is not unlike hearing a symphony that moves you to tears, and attempting to isolate just what particular instrument evoked that reaction. Was it the strings, the horn section, the flute? Or was it the combination of all the instruments, the way they were played, the way the music was written?
Researchers in nearly every study seem to agree that extracting a certain vitamin from foods and expecting them to perform as they do as part of an overall healthy diet is ineffective, because the positive effect of vitamins in found in foods seem to work in concert with all the other micronutrients they contain, in ways science hasn’t been able to discover.
Of course, you’ll hear many testimonials to vitamin supplementation from ordinary people who swear that vitamin such-and-such cured their eczema, or maintain they’ve never had a cold since they started megadosing vitamin C. Unfortunately, anecdotes are not empirical evidence.
The bottom line? If you want to spend your money on vitamin supplements, that’s your choice, as long as you’re aware of the risks involved with some vitamins and supplements, which we can help you evaluate.