Iron deficiency anemia is a public health problem with a high prevalence in the world (~30%), especially in children and women. The iron absorption depends of dietary factors and iron stores; some foods such as polyphenols and tannins inhibit the iron absorption, while antioxidants such as vitamin C improve iron absorption. Blueberries contain significant amounts of antioxidants and polyphenols. The aim of this experiment was to evaluate the effect of blueberries on non-hem iron bioavailability.
Experimental study conducted in 14 healthy women (36-51 years old) using radioactive iron isotopes (55Fe y 59Fe). On day 1, 5 mg of Fe (as FeSO4) was administered; on day 2, 5 mg of Fe with 100 g of blueberry was given, on day 14, 2.4 mg of Fe with 100 g of blueberry and 100 g of bread with 30 g of cheese and 5 g of butter (breakfast, total Fe = 2.6 mg) was administered; on day 15, 2.4 mg of Fe with breakfast were given. On days 14 and 28 blood samples were taken to measure the iron nutritional status and iron absorption.
None of the volunteers presented iron deficiency anemia. The geometric mean (range ± 1 SD) of basal iron absorption was 30.2% (13.8- 66.0). The absorption of iron plus blueberries, blueberries and breakfast, and breakfast were 6.8% (21.1-21.7), 7.5% (2.3-24.0), and 5.7% (1.5-22.4) respectively (ANOVA, p<0001).
According to the results, blueberries with, and without breakfast significantly diminished non-hem iron absorption. Support by Fondecyt Chile 1130090