Apple seeds

Toxicity of apple seeds

Despite the well-known saying "An apple a day keeps the doctor away”, Few are aware that the ingestion of large quantities of apple seeds can cause the death of the subject.These seeds, in fact, are rich in amygdalin (or vitamin B17), a cyanogenic glycosidic compound that is extremely toxic when subjected to enzymatic hydrolysis: in fact, following a hydrolytic chemical reaction, amygdalin releases hydrogen cyanide, the ingestion of which can cause intoxication and poisoning of various entities, based on the amount ingested.

Lethal dose

It is estimated that the LD 50 (average lethal dose) of hydrogen cyanide taken orally (oral ingestion) is around 50 mg / kg of body weight: massive doses cause instant death due to respiratory arrest in a few seconds. In other words, it is believed that only half a cup of apple seeds is enough to kill an adult, while a child could risk death even with much lower doses of apple seeds. However, each apple contains a minimal amount of seeds, so involuntary intoxication is almost rare.

Effects in the body

The most alarming problem of apple seeds is not amygdalin itself, as it is not very reactive: amygdalin, however, is able to react with a particular enzyme (beta-glucosidase) and, following the degradation of the substance through hydrolysis , release hydrogen cyanide (in addition to two molecules of glucose and one of benzaldehyde). Amygdalin taken orally is 40 times more dangerous and toxic than the same dose injected intravenously: this is explained by the fact that, although man does not directly produce beta-glucosidase enzymes in the organism, the bacterial flora is still capable of degrading amygdalin thanks to some similar beta-glucosidase enzymes.
Apple seeds are rich in amygdalin: the enzymes of the bacterial flora degrade the substance into toxic compounds including, in fact, hydrogen cyanide. The latter, in massive doses, causes intoxication and poisoning, which causes death by cellular asphyxia.
The toxicity of apple seeds - as well as that of grape seeds, pear and Rosaceae in general - should not be underestimated. Non-lethal quantities of amygdalin, therefore converted into hydrogen cyanide, can still cause undesirable effects: excitement alternating with depression, breathing difficulties, stupefaction, glassy eyes, dilation of the pupils, convulsions, spasms and coma.