1. Apple Seeds are Poisonous
Apple seeds contain something called amygdalin, which converts into deadly cyanide when the seeds are chewed or crushed. It’s an effective defense mechanism for the fruit because cyanide interferes with the oxygen supply going to your body’s cells, and can kill a person within minutes at a high enough dose.
Accidentally eating a seed or two won’t kill you, but it can cause negative health effects such as dizziness, weakness, confusion, headache, nausea, vomiting, and stomach cramps. But don’t worry if you just swallowed the seed without chewing it. In this case, it is likely to pass through your system undigested. It is only when the seeds are crushed that the conversion to cyanide takes place.