The researchers from the University of Eastern Finland and the University of Minnesota wanted to find out if taking supplements had any effect on people from a "well-nourished" population--in this case, Americans. They looked at 38,772 surveys from women averaging an age of 62 from the Iowa Women's Health Study. These women reported their use of supplements in 1986, 1997, and 2004.
The study's results showed that the women who took supplements also lived healthier lifestyles: they were more likely to go on low-fat diets and exercise, and they were less likely to smoke. Despite all this, however, the researchers discovered that they had a higher risk of mortality compared to those who didn't take supplements.
"We found that several commonly used dietary vitamin and mineral supplements, including multivitamins, vitamins B6, and folic acid, as well as minerals iron, magnesium, zinc, and copper, were associated with a higher risk of total mortality," they wrote in the study.
While the researchers have yet to figure out why exactly supplements increased older women's chances of dying, they noted that iron recorded the most likelihood of increased mortality. They also mentioned, though, that one possible reason for iron users' mortality risk is that they might be taking the supplements for medical conditions they might have.
"We cannot recommend the use of vitamin and mineral supplements as a preventive measure, at least not in a well-nourished population," Dr. Goran Bjelakovic of the University of Nis in Serbia and Dr. Christian Gluud of Copenhagen University Hospital in Denmark wrote in a commentary for the study.
Want to read more articles about vitamins? Read on:
- What You Should Know about Taking Vitamins and Food Supplements
- Vitamin ABCs: Which vitamins should you really be taking?
(Photo source: sxc.hu)