I am a big fan of some vitamin supplements – notably vitamin D – which many people living urban lives tend to get significantly too little of. But there is some recent bad news about vitamin supplements. The first piece is that a large study suggests that there is a very slight link between taking large doses of vitamin E and an increased risk of prostate cancer in men.
But a closer look does make the link seem very tenuous at best. Basically in a large study, men who took very large daily doses of vitamin E were shown to have a 1% increased risk of prostate cancer. The difference is slight but definitely there since the study was done over time with a very large test group and a very large control group.
The second piece of bad news is that taking multivitamins for a long time has absolutely no effect on longevity in women. This study looked at vitamins A, B, C, D, E and beta carotene, selenium, calcium, copper, magnesium and zinc. But there was one exception – for women, taking calcium led to a 6% decrease in mortality over a 19 year period.
Since the differences in these studies are small (apart from better health for women who take calcium), the results still have to be regarded as a little suspect. Certainly for anyone at risk of getting two few vitamins or minerals, supplements can be a great help. In addition, some vitamins like vitamin D are beginning to be better understood and the RDA for them is being increased. But conversely there is no need to overdo it and take massive doses of vitamins.