The number of apple seeds that could kill a human is extremely high and depends on several factors, including whether the seeds are chewed (which releases cyanide) and the person's body weight.
- Apple seeds contain amygdalin, which breaks down into hydrogen cyanide (HCN), a highly toxic substance
- The fatal oral dose of cyanide is estimated to be about 1–2 mg per kg of body weight. For a 70 kg (154 lbs) adult, this translates to roughly 39–140 mg of cyanide
- Each apple seed contains a very small amount of cyanide, approximately 0.5 mg or less, but only if the seed is crushed or chewed to release it
- According to calculations shared on Reddit, it would take around 140,000 to 250,000 apple seeds to reach a fatal dose of cyanide if all seeds were chewed and the cyanide fully released
- Since an average apple contains about 5 seeds, this means consuming seeds from roughly 28,000 to 50,000 apples would be required for a lethal dose
- If the seeds are swallowed whole without chewing, the risk is much lower because the amygdalin is less likely to be converted to cyanide in the digestive system
In summary, it is practically impossible to die from apple seed poisoning by normal consumption, as you would have to ingest and thoroughly chew an extraordinarily large number of seeds (on the order of hundreds of thousands) to reach a lethal dose. However, it is still advised to avoid chewing or consuming large quantities of apple seeds due to the cyanide content
