Plants make poisonous chemicals to protect themselves from being eaten.

Scientists found that old types of broccoli had more genetic variety than modern ones, and many of those lost genes help the plant make natural chemicals to fight off bugs and diseases—so yes, plants make these chemicals to protect themselves.

Plants make chemicals like tannins and oxalates to protect themselves from being eaten or infected, and this study confirms those chemicals exist—even if it’s asking whether they’re bad for people.

Plants make their own natural poisons to keep animals and germs from eating them, and this study says most of the pesticide residue in our food comes from these plant-made chemicals, not human-made ones.