Why a Green Tint on Your Potato Is a Warning Sign of Poison

Solanine is a natural pesticide that the potato plant produces to protect itself from insects, fungi, and hungry herbivores. In a healthy, fresh potato, the levels of this toxin are usually low enough to be processed by the human digestive system without any noticeable effect. However, when the potato turns green or begins to grow sprouts (eyes), the concentration of solanine skyrockets, particularly in the skin and the area immediately surrounding the sprouts. Unlike many other foodborne pathogens or toxins that are neutralized by heat, solanine is heat-stable, meaning that boiling, baking, or frying the potato will not eliminate the poison, making the green sections hazardous regardless of the cooking method.