I feel like this is based on this string of posts, but there’s also a handy-dandy chart from the USDA (page four) in that thread that discusses what foods this is true for and which it is not. Honestly, I feel like people who say this stuff have never been food insecure or poor as shit and not in a position to throw out food that can be saved. 

So yeah, don’t eat mold. But if you are not in a position to just throw away food if it can be safely eaten, check this chart. 

Basically, it looks like the moisture content is the biggest determinant. Just. Be careful. OK? And don’t get your science only from tumblr. 

I can’t believe people need to be reminded of this.