>>15861918
As a follow-up anon. It looks like Portabellas and others have compounds that can be mutagenic(meaning cause cancer), however cooking them eliminates this and actually some or most help inhibit cancer and a host of other maladies. So I guess the follow-up is don't eat mushrooms raw unless you know what is in them.
Mushrooms
Mushrooms, even common button mushrooms, contain traces of carcinogenic compounds in raw form. The same toxin, hydrazine, is also found in portobello mushrooms, and shiitake mushrooms contain a naturally occurring formaldehyde. Both chemicals are heat-sensitive and abolished upon exposure to heat. You might think nothing of eating a few slices of button mushrooms raw, but to get the anti-cancer effects of mushrooms, eat them cooked. A 2009 study published in the International Journal of Cancer found that regular consumption of cooked mushrooms has been shown to decrease the risk of breast cancer by 60 percent.
https://www.vegetariantimes.com/guides/4-plant-foods-you-should-cook-before-eating/