>>19478394They contain things like phytic acid which has the molecular structure similar to a snowflake and it grabs nutrients and makes them unusable. You can mitigate it sometimes like in legumes by soaking it so it turns to phytates and becomes less of an anti-nutrient.
I think a lot of Mexican peoples bloodlust might be a product of them being deficient in nutrients., kind of like how vegans cover their food in red sauces to trick their brain into thinking they're consuming animal products/blood.