Another vitamin hypothesis debunked

Vitamin supplements - probably ineffective

A recent large Australian study has demonstrated that giving vitamin C and vitamin E supplements did not prevent pre-eclampsia in pregnant women or help the babies. The results have been published in the most recent issue of the New England Journal of Medicine (Vol 354:1796-1806).

It had previously been hypothesised that the use of these agents could help decrease the risk of pre-eclampsia, which is a potentially life-threatening form of hypertension in pregnant women. Pre-eclampsia also frequently leads to intrauterine growth retardation in the foetus as well as premature birth, something that the vitamin supplements were hoped to help prevent as well.

Unfortunately, in the study of 1900 Australian women in the University of Adelaide, it appears that there is no beneficial effect.

The past several years have not been good evidence-wise for the proponents of the “vitamins for health” crowd, with a number of large studies finding supplements in general to be useless in the otherwise healthy individual.

• A large meta-analysis last year illustrated that despite “common wisdom”, mega doses of vitamin C does not help prevent the common cold.
• The seminal “Heart Protection Study” which had an antioxidant arm definitively showed that taking a battery of antioxidants (vitamin E, vitamin C and beta-carotene) made absolutely no difference to cardiovascular endpoints or all cause mortality.
• Two trials looking at using beta-carotene supplements as a protective agent (against cancer) in smoking showed that take they actually significantly increased the rate of lung cancer!
  

With the results of the latest study, there is even less evidence for the usage of vitamin supplements.

The evidence for vitamin supplements in vitamin replete individuals is scanty. At best, the usual vitamin tablets work as a placebo and are usually harmless (though the beta-carotene studies should send a shiver down every smoker’s spine). The average person should aim to get their vitamins and minerals from a varied and healthy diet and save the money spent otherwise on mostly useless supplements on something else.

Source articles:
New England Journal of Medicine: Rumbold A., Crowther C., et al.
Vitamins C and E and the Risks of Preeclampsia and Perinatal Complications. NEJM Volume 354:1796-1806 April 27, 2006 Number 17

From: The Sydney Morning Herald
No effect from extra pregnancy vitamins (excerpt)
April 28, 2006 - 5:09PM

...Giving extra vitamins C and E to pregnant women does not prevent high blood pressure problems or benefit their babies, Australian researchers have found...

...They found that treating pregnant women with vitamin supplements did not help their babies nor stop them developing pre-eclampsia.

Pre-eclampsia, which affects about six per cent of women in their first pregnancy, is a disorder that occurs in the second half of pregnancy and is characterised by hypertension and protein in the urine.

It carries the risk of serious complications and death to both mother and baby, including premature birth and poor intrauterine growth.

Study leader Caroline Crowther said pregnant women at risk of developing pre-eclampsia had previously been treated with vitamins C and E.

Dr Crowther said such treatment had also previously been thought to have kept babies healthy and reduce the risk of them not growing...

..."We do not recommend that women take these extra supplements...."