UPDATE - Issue 30 - Summer 2007
Multivitamins - Good or Bad?
There was a fair amount in the press during June suggesting that taking multivitamins might be a serious mistake. The BBC web site had a headline 'Multivitamin Prostate Warning.'
The source of this scare was a large US study that looked into this question. Almost 300,000 men who were cancer free in 1995 and 1996 were followed up over five years. Their multivitamin use was assessed via a self-administered mailed questionnaire. Over the five-year period some of this large number were diagnosed with prostate cancer. The study tried to correlate multivitamin consumption with the occurrence of cancer. The authors concluded that there was nothing to suggest that multivitamin use is associated with a risk of early or localized disease. They did discover, however, that men taking excessive levels of multivitamins along with other supplements have an increased risk of developing advanced prostate cancer. The risk of dying from the disease is apparently double among those taking multivitamins seven days a week compared to those taking none. The authors, themselves, rather mildly, say that this is of concern and warrants further study.
Nearly a quarter of adults in the UK take antioxidant supplements or multivitamins. The market for such products is approaching half a billion pounds per year. Despite the size of the market and the number of people involved there are still many gaps in our knowledge of the action of antioxidant supplements. How much fruit and vegetables do we have to eat to obtain an optimal amount of these nutrients? Why should it not be possible to take a vitamin pill to obtain the same effect as a balanced diet?
Notwithstanding the above, the weight of research evidence indicates that Lycopene (15mg), Vitamin E (400iu), Selenium (200µg) taken daily plus, of course, a balanced diet, regular exercise and a body mass index less than thirty are all collectively beneficial.
RDAs and EVMs
There may be some confusion over recommended daily allowances (RDA) for vitamins and minerals all of which are considerably less than the figures we quote in the above article.
The RDA is the minimum amount needed to avoid a deficiency. For example, taking less than the RDA for Vitamin C over a period might lead to the development of scurvy. The RDA says nothing about the optimum amount that should be consumed.
The UK Expert Group on Vitamins and Minerals (EVM) has published a table of the safe upper levels of each vitamin and mineral that may be taken daily. This table may be found on page 15 of the document on the Government web site: www.food.gov.uk/multimedia/pdfs/fsis1206.pdf.
Our thanks to supporter Geoffrey Everett for encouraging us to research this article.