Nothing. Absolutely nothing. Doubly so if you aren't eating animal products.

I'll add that avoiding all animal products has its own perils, namely the sort that results in vitamin deficiencies. And while a diet filled with whole grains and mostly plant-based foods is considered healthy, we simply don't know enough about nutrition to have one way or another. Or even to get vitamin doses right. I say all this while eating mostly vegetarian myself. I eat fish about once a week. I don't like it so much, but it is healthy.

wheat contains Phytic acid for example: https://en.wikipedia.org/wiki/Phytic_acid which can be reduced with the correct dough process.

The beta-carotene in carrots is fat soluble and the cells are pretty robust, so you get more out of them if you cook them in fat.

Champignons contain a mild poison, which is not deadly for humans but destroyed when heated, digestibility increases too.