Regular Consumption of High Phytate Reduces Inhibitory Effect of Phytate on Iron Absorption

Phytate is one of the main inhibitors of nonheme iron absorption. High phytate consumption is of concern in developing countries because of the high prevalence of iron and zinc deficiency in these countries. In this study, we investigated the effect of habitual consumption of a high phytate diet on the inhibitory effect of phytate on nonheme iron absorption. Thirty-two non-anemic female subjects with ferritin ≤ 30µg/L were randomized into two groups, after matching for ferritin concentration. Each group consumed either high or low phytate foods that were provided for 8 wk. Iron bioavailability from a high phytate test meal was measured using area under the curve (AUC) for serum iron at baseline and after the intervention.

Inclusion criteria

• Marginal iron status (Serum ferritin <30ug/L)
• BMI in the range 18.5-24.9kg/m2
• Willing to modify diet to increase or decrease phytate intake
• Willing to give multiple blood samples at beginning and end of study

Exclusion criteria

• Pregnant
• Lactating
• Smoker
• Anemic (hemoglobin <120 g/L)
• Has gastro-intestinal disease/condition that can affect absorption