It is important for people to be aware that certain fruits contain poisonous seeds, which are obviously not to be consumed. Moreover, it takes fewer seeds for children to be poisoned than adults.
The seeds in apples contain a chemical that releases cyanide into the body when ingested. Eating many apple seeds can be dangerous.
According to the Bio-Medicine website, apricot seeds contain cyanide and can cause death if too many seeds are ingested in a short period of time. Consuming a couple of seeds should not hurt an adult.
Cherry seeds are stones that contain cyanide. It is best to avoid them. One stone should not hurt an adult, but consuming many could cause dizziness, vomiting or even death.
Plum pits contain cyanide as well, and should not be consumed in high quantities.
Peaches have pits that contain cyanide. Tough skins covering the pit deter most people from eating them. Eating only one pit would not do any harm.