Today at the American Heart Association meeting, a study was presented evaluating whether a daily multivitamin would confer cardiovascular protection. The study was large and well done – it followed 14,641 men age 50 and older for an average of 11 years. Vitamins had no benefit on preventing heart disease or death.
In all fairness to vitamins, there was a small benefit in preventing cancer for those taking multivitamins. For 1,000 people taking vitamins or placebo for one year, 17 vitamin-takers would get cancer versus 18.3 cases of cancer in placebo-takers. Of note, there was no difference in mortality from cancer or in overall mortality from any cause for vitamin-takers.
There have been multiple vitamin fads in the past. Several years ago it as vitamin E to prevent stroke. When studied in controlled scientific trials, it was determined that there was no benefit.
More recently, there was an increase in the use of folate (vitamin B9), which lowers homocysteine blood levels. High levels of homocysteine are associated with higher risk of myocardial infarction (aka MI or heart attack). As with vitamin E, clinical trials showed that folate also has no benefit.
It seems to me that there is a natural desire that people have to want to believe in vitamins. I chalk it up to a combination of good marketing coupled with a societal urge to believe in healthy, natural living. Western diets tend to be pretty rich, and foods nowadays are fortified with additional vitamins.
For those who would argue that the hint of cancer risk reduction is sufficient to lead them to take a multivitamin, I suggest that they should take an aspirin (or baby aspirin) daily. The evidence and benefit are far greater – not only does aspirin appear to have cancer-preventative properties, it also lowers the risk of cardiovascular events. But even without aspirin as an alternative, the data appear to me to be nebulous at best and do not justify taking a daily multivitamin.
Vitamin makers are very happy to see you take your vitamins. Your heart (and the rest of your body) probably doesn’t care.
sources: JAMA: Multivitamins in the Prevention of Cardiovascular Disease in Men; JAMA: Multivitamins in the Prevention of Cancer in Men; JAMA: Effects of Homocysteine-Lowering With Folic Acid Plus Vitamin B12 vs Placebo on Mortality and Major Morbidity in Myocardial Infarction Survivors; AHA/Circulation: Antioxidant Vitamin Supplements and Cardiovascular Disease