What are some substances that can interfere with absorption of minerals?
Phytate, tannins, and oxalates can all interfere with absorption of minerals.
Phytate is an organic compound found in whole grains, bran, and soy products which can bind minerals and limit their absorption.
Oxalates are organic acids found in spinach, other leafy greens, chocolate, rhubarb which can interfere with iron anc calcium absorption.
Not really sure how tannins work.