Popular Supplements May Increase Death Risk


A recent study of almost 40,000 older women examined the association between vitamin and mineral supplement use and death rates.  The study showed that some common supplements appear to actually increase the risk of dying. Finnish and American scientists found that multivitamins, vitamin B6, folic acid, iron, magnesium, zinc, and copper, were all associated with increased risk of death in older women. Conversely, they found that the use of calcium reduced the risk of death.

The Research

38,772 older women from the Iowa Women’s Health Study were surveyed on their vitamin and mineral supplementation practices in 1984 (average age 61.6 years), 1997, and 2004. Through to the end of 2008, deaths were identified through the State and National authorities with 40.2% of the original women having died. The statistical analyses adjusted for levels of education, health risk factors such as high blood pressure and diabetes, smoking status and levels of physical activity.

The Results

The use of multivitamins increased the risk of death by 2.4%, vitamin B6 by 4.1%, folic acid by 5.9%, iron by 3.9%, magnesium by 3.6%, zinc by 3.0% and copper by 18.0% when compared to non-use. In contrast, use of calcium decreased risk of death by 3.8%.

So What?

Given that more than 30% of adults from high-income countries like ours take vitamin and mineral supplements, these results strongly suggest that eating a well-balanced and more natural diet emphasising a range of coloured natural foods is the way to go. The researchers in this study concluded that they see little justification for the general and widespread use of dietary supplements. However, they do suggest that they be used with a medically-based cause such as symptomatic nutrient deficiencies. Bottom line is ensure that you eat a well-balanced diet that takes into account your age, health status, training intensity and volume. If in doubt, visit an accreditted sports dietitian.

Source: Mursu, J. and others. (2011). Dietary supplements and mortality rate in older women: The Iowa Women’s Health Study. Archives of Internal Medicine. 171: 1625-1633.