I think it's quite accepted the idea that phytates are harmful due to the way they hinder the absorption of minerals. But how does that happen? Is it limited to the food that is digested together with them or it has an effect on the food that is digested later? For instance, if I eat whole wheat pasta at lunch and a big grass-fed steak at dinner how do the phytates I ingested at lunch affect the minerals I ingest at dinner?
Phytic acid chelates (or binds to) minerals such as iron, zinc, magnesium, etc. in the digestive tract and makes them non-absorbable. It is unlikely that after 4-5 hours that the phytates from one meal would affect a subsequent (or previous) meal.
There is some evidence that if your gut flora are up to snuff, the phytase they produce eliminates the problem altogether. See this post:
However, whole wheat pasta is not to be recommended, even if phytates and gluten/gliadins/WGA are not an issue for you. It's just suboptimal nutritionally.
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