Phytates (and phytic acid) are antioxidant compounds found in whole grains, legumes, nuts and seeds. The chief concern about phytates is that they can bind to certain dietary minerals including iron, zinc, manganese and, to a lesser extent calcium, and slow their absorption. Phytates in your everyday meals should not be an issue for you as long as you’re eating a balanced diet. Most of us consume enough minerals in common foods to more than make up for the small amounts of these micronutrients that might be tied up by phytates. The only individuals who might need to be careful are vegetarians who consume a lot of wheat bran, which is a concentrated source of these substances. Phytate-associated deficiencies of iron and zinc do occur in some third-world countries where people mostly eat grains.

He meant green leafy vegetables