Can green tomatoes be eaten after turning red? Are they toxic?

Green tomatoes that have ripened and turned red are generally safe to eat and typically non-toxic.

Unripe green tomatoes contain a naturally occurring toxic compound called solanine. Solanine serves as a plant’s natural defense mechanism against pests and pathogens due to its antimicrobial and insecticidal properties. However, if ingested by humans, it can strongly irritate and corrode the gastrointestinal mucosa, exert a paralyzing effect on the central nervous system, and cause hemolysis (destruction of red blood cells). This may lead to acute gastroenteritis, with symptoms such as diarrhea, nausea, vomiting, excessive salivation, and abdominal pain. Typically, tomatoes ripen and turn red within about one week; during this process, the solanine content in green tomatoes gradually decreases until it becomes undetectable—indicating full ripeness and loss of toxicity. At this stage, they are generally safe for consumption and unlikely to cause adverse health effects.

In daily life, there exists a special tomato variety that remains green even when fully ripe. Such tomatoes are generally safe to eat and are rich in anthocyanins, which possess potent antioxidant properties.