Another example: oxalic acid. Like phytic acid, oxalate binds to iron and interferes with its absorption. While phytate is found mainly in grains, oxalate is found in tea, spinach, rhubarb, and sardines -- all paleo foods. I mention these foods because they are rich enough in oxalate that doctors typically tell people to avoid them if they have a problem with oxalate kidney stones. Todd Moody Would these foods be plentiful enough, in nature, to wreck as much havoc on a human, who eats a much broader food range, and has a stronger immune system? I would think that phytates and an agrarian diet would be far more detrimental to health. In small amounts, oxalate, is probably handled well by a paleo eater, who occasionally comes upon types of food with oxalates. The oil is not very likely to be paleo any how. Whole foods are, and we need to look at the amount of consumption of any one type of food, as it would be found in nature, on average.