Two studies published in the Annals of Internal Medicine showed that multivitamins did not provide protection against cognitive decline or cardiovascular disease. The Physicians’ Health Study involved more than 5,000 older male doctors who were randomly assigned to take either Centrum Silver or a placebo. They started taking their pills in 1997 and were assessed four times over the next dozen years. Investigators tested verbal memory and cognition. There was no difference in cognitive performance between the two groups. The authors concluded that long-term use of a daily multivitamin is not effective for preventing cognitive decline.
In the second study, 1,700 people who had experienced a heart attack were randomly assigned to a high-potency multivitamin or placebo. They were followed for roughly five years. Again, there was no difference in cardiovascular outcomes between the two groups. An editorial in the Annals concluded that vitamins are a waste of money, that most supplements do not prevent chronic disease or death and their use is not justified.
[Annals of Internal Medicine, Dec. 17, 2013]
This stands in contrast to some previous findings. The very same Physicians’ Health Study that found no benefit of multivitamins for cognitive function found that they did help reduce the risk of cataracts. A recent study also found that people with chronic obstructive pulmonary disease (COPD) experience less muscle fatigue if they take vitamin C. So we think it is premature to dismiss vitamins as having no value whatsoever.
Many people take medications that can deplete their bodies of critical vitamins, as the acid-suppressing drugs deplete vitamin B12.