Older women who take vitamins ‘are more likely to die early

OLDER women are increasing the risk of death by taking certain dietary supplements, a new study has revealed.

Research published in the Archives of Internal Medicine, says supplements, including multi-vitamins, folic acid, iron and copper, among others, appear to be associated with a greater risk of death.

The authors say the use of dietary supplements has increased considerably over the last decade.

Dr Jaakko Mursu, of the University of Eastern Finland and the University of Minnesota, and colleagues used data collected during the Iowa Women’s Health Study to examine the association between vitamin and mineral supplements and mortality rates among 38,772 older women with an average age of 61.6.

Dr Mursu said: “Based on existing evidence, we see little justification for the general and widespread use of dietary supplements. We recommend that they be used with strong medically based cause, such as symptomatic nutrient deficiency disease.”

Supplement use was self- reported in 1986, 1997 and 2004 via questionnaires. Among the women who started the first survey in 1986, 15,594 deaths (40.2 per cent) occurred over an average follow-up time of 19 years.

Dr Mursu and his team’s research found that use of most supplements was not associated with reduced total mortality in older women, and many supplements appeared associated with increased mortality risk.

After adjustment, use of multivitamins, vitamin B6, folic acid, iron, magnesium, zinc and copper, were all associated with increased risk of death in the study population. Conversely, calcium supplements appear to reduce the risk of mortality.

The association between supplement intake and mortality risk was strongest with iron. The findings for both iron and calcium supplements were replicated in separate, short-term analyses with follow-up occurring at four years, six years and ten years.

Doctor Goran Bjelakovic, of the University of Nis in Serbia, said the findings “add to the growing evidence demonstrating that certain antioxidant supplements, such as vitamin E, vitamin A, and beta-carotene, can be harmful”.

He added: “Dietary supplementation has shifted from preventing deficiency to trying to promote wellness and prevent disease.

“Older women – and perhaps men – may benefit from intake of vitamin D3 supplements, especially if they have insufficient vitamin D supply from the sun and from their diet. The issue of calcium supplements may require further study.”

Dr Glenys Jones, a nutritionist with the Department of Diet and Population Health at the MRC Human Nutrition Research, Cambridge, said: “This observational study is interesting, but it does not show that supplement use causes women to die earlier. The study does not take into account whether the women using the supplements are doing so in response to illness, for example, using iron supplements in response to anaemia. It is most likely the illness that is the cause of the women dying, not the supplement use.”