Breaking down phytic acid in cereals improves how much iron the body can absorb, but the amount of improvement varies by cereal type: maize and wheat show the biggest gains, while rice and oats show...
Mechanism
Synthesis from 1 study
Phytic acid in cereals locks away iron so your body can't absorb it. When that acid is broken down, the iron gets freed up — and the more acid there was to begin with, the more iron becomes available. That’s why maize and wheat show the biggest gains: they started with the most locked-up iron.
Most probable mechanism
When phytic acid in cereal grains is broken down, it stops trapping iron so the body can absorb it. Cereals like maize and wheat start with a lot more phytic acid, so breaking it down frees up much more iron than in cereals like rice and oats, which had less to begin with. That’s why the improvement in iron absorption is much bigger in maize and wheat.
Phytic acid in cereal matrices forms insoluble complexes with dietary iron, rendering it unavailable for absorption in the small intestine.
Enzymatic degradation of phytic acid breaks these complexes, releasing free iron ions into the intestinal lumen.
Free iron ions are reduced to ferrous form and transported into intestinal cells via divalent metal transporter 1.
The amount of iron released and subsequently absorbed is directly proportional to the initial concentration of phytic acid in the cereal matrix.
Evidence from Studies
Supporting (1)
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Degradation of phytic acid in cereal porridges improves iron absorption by human subjects.
Contradicting (0)
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