Omega-3 and Iron: Important Partners for Fighting Iron Deficiency
Iron is an essential mineral that plays many important roles in the body including functioning as a component of hemoglobin, supporting metabolism, growth and the immune system. In the United States and many other countries, flour and/or grains are fortified with iron and are an important source of iron in the diet. Despite fortification, iron deficiency is the most prevalent nutritional disorder worldwide. In resource poor areas iron deficiency anaemia can be aggravated by infectious diseases. However there is also evidence that iron supplementation can increase morbidity from acute and chronic infections. This has generated a lot of controversy and debate about how to address iron deficiency anaemia in areas with high rates of infectious disease.
In addition to iron, long chain omega-3 fatty acids are important for immune function and are incorporated into immune cell membranes. Malan and colleagues hypothesized that providing omega-3 supplements in combination with iron may help mitigate illness in iron-deficient children. Over a period of 8.5 months 321 South African children aged 6 to 11 were randomized to one of four intervention groups: 1) iron and placebo, 2) omega-3 (EPA + DHA) and placebo, 3) iron and omega-3 or 4) placebo and placebo.
Compared to group 4 (placebo+placebo) iron supplementation increased the number of days ill and the number of days with respiratory related illnesses. Conversely, omega-3 supplementation decreased the number of days with illness. What happened then when omega-3’s and iron were provided together? Iron status improved but the number of days with illness was similar to placebo. This importantly suggests that the increase in morbidity with iron supplementation may be prevented when given in combination with omega-3 fatty acids. This simple supplementation strategy has the potential to have a large impact on public health.
The other important takeaway from the study by Malan is that it is important to think about nutrients in a synergistic way. Nutrients often have complementary benefits and as highlighted in this study and a previous Talking Nutrition post, may work better together.
Malan J et al. n-3 Long chain PUFAs reduce respiratory morbidity caused by iron supplementation in iron-deficient South African schoolchildren : a randomized, double-blind, placebo-controlled intervention. Am J Clin Nutr 2015, doi:10.3945/ajcn.113.081208
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Harding KB, Neufeld LM. Iron deficiency and anemia control for infants and young children in malaria-endemic areas: a call to action and consensus among the research community. Adv Nutr 2012, doi:10.3945/an.111.000769
Calder PC. n-3 Fatty acids, inflammation and immunity: new mechanisms to explain old actions. Proc Nutr Soc 2013, doi:10.1017/S0029665113001031