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 amounts of apple seeds can cause the death of the subject. These seeds, in fact, are rich in amygdalin (or vitamin B17), an extremely toxic glycosidic compound when subjected to enzymatic hydrolysis: in fact, following a hydrolytic chemical reaction, the amygdalin releases cyanidric acid, whose ingestion can cause intoxication and poisoning of varying degrees, based on the amount ingested.

Lethal dose

It is estimated that the LD 50 (average lethal dose) of cyanidric acid taken orally (oral ingestion) is around 50 mg / kg of body weight: massive doses cause instant death by 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 doses of much lower apple seeds. However, each apple contains a minimum amount of seeds, so involuntary intoxication is almost rare.

Effects in the body

The most alarming problem of apple seeds is not the amygdalin itself, since it is not very reactive: amygdalin, however, is able to react with a particular enzyme (beta-glucosidase) and, following the degradation of the substance by hydrolysis, to release hydrocyanic acid (in addition to two molecules of glucose and one of benzaldehyde). The oral amygdalin is 40 times more dangerous and toxic than the same intravenous dose: this is explained by the fact that, although man does not directly produce beta-glucosidase enzymes in the body, the bacterial flora is still able to degrade amygdalin thanks to some similar beta-glucosidase enzymes.

Apple seeds are rich in amygdalin: the enzymes of the bacterial flora degrade the substance in toxic compounds including, indeed, hydrocyanic acid. The latter, in large doses, causes intoxication and poisoning, which causes death by cell asphyxia.

The toxicity of apple seeds - as well as that of grape seeds, pear and Rosaceae in general - must not be underestimated. Non-lethal quantities of amygdalin, therefore converted into cyanidric acid, can still cause undesirable effects: excitation alternated with depression, difficulty breathing, stupefaction, glazed eyes, dilation of the pupils, convulsions, spasms and coma.