Adding a specific amount of phytic acid to white-wheat bread lowers how much magnesium the body can absorb from the bread, which may reduce the availability of this mineral in diets that rely heavily...
Mechanism
Synthesis from 1 study
Phytic acid in bread grabs onto magnesium in your gut and locks it into a form your body can't absorb. That magnesium then leaves your body in stool instead of entering your bloodstream, so you end up with less of it available for your cells.
Most probable mechanism
When phytic acid is eaten with food, it binds tightly to magnesium in the gut, forming a solid compound that the body cannot absorb. This bound magnesium passes through the digestive tract and is removed in stool instead of entering the bloodstream, so less magnesium becomes available for the body to use.
Phytic acid dissociates from food matrices in the intestinal lumen under physiological pH conditions
Phytic acid chelates free magnesium ions to form insoluble phytate-magnesium complexes
The insoluble complexes remain in the intestinal lumen and are not transported across the intestinal epithelium by enterocytes
Magnesium contained in the complexes is excreted in feces, reducing the amount available for systemic uptake
Evidence from Studies
Supporting (1)
Community contributions welcome
Phytic acid added to white-wheat bread inhibits fractional apparent magnesium absorption in humans.
Contradicting (0)
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Gold Standard Evidence Needed
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