Women with increased iron intakes may have a better physical performance

According to a new Australian review a daily iron supplementation significantly improves maximal and submaximal exercise performance in women of reproductive age.

The review and meta-analysis included 22 randomized controlled trials which measured the exercise per- formance (maximal aerobic capacity) of a total of 911 women (aged 12 to 50 years) who took a daily
iron supplement or placebo (1). The analysis indicated that women who supplemented iron (30 to over
100 mg/day for one to more than three months) showed a significantly improved maximal and submaximal exercise performance compared to the placebo group. These benefits were clearest in iron-deficient and trained women.

The researchers commented that these findings have implications for clinical management of patients, nutritional optimization for athletes, and rationale of public health anemia control programs. The prevention and treatment of iron deficiency could improve performance in female athletes who compete in a wide range of sports requiring either or all of endurance, maximal power output, and strength. The physiologic mecha- nism for these effects may reflect a range of processes. For example, raised hemoglobin concentrations due to increased iron intake may improve oxygen-carrying capacity and hence tissue oxygenation during exercise. Women of reproductive age are at high risk of iron deficiency and iron deficiency anemia due to menstrual blood losses. Female athletes are at particular risk because of diets deficient in iron, increased losses due to gastrointestinal bleeding, and reduced iron absorption due to subclinical inflammation (2).

1. Pasricha S.-R. et al. Iron Supplementation Benefits Physical Performance in Women of Reproductive Age: A Systematic Review and Meta-Analysis. The Journal of Nutrition. Published online April 2014.
   
2. Peeling P. et al. Athletic induced iron deficiency: new insights into the role of inflammation, cytokines and hormones. Eur J Appl Physiol. 2008; 103:381–391.