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"An apple a day keeps the doctor away." True enough. However, apple seeds contain a substance that can convert into poisonous hydrogen cyanide in the intestine. But there is no need to panic. The chance of consuming enough apple seeds to produce a toxic effect is slight, and proper handling can reduce the risks further.

Fruit Seed Poisons

Peaches, plums and apples all have pits or seeds that contain toxins.

Apples are only one of a number of fruits that contain amygdalin in their seeds. The biggest offenders are apricot and peach pits, followed plums, apple seeds, almond and quince, in descending order of amygdalin content. The amount of amygdaline contained in apple seeds is tiny, and the seed must be chewed up to release the substance.

Amygdalin

Cassava has a high cyanogen content.

Amygdalin is a glycoside toxin that combines with a gastrointestinal enzyme to produce hydrogen cyanide, the same poison that was called Cylon B and used for mass executions in concentration camps during World War II. Very often, the fruit or seed with amygdalin, and other precursors to cyanide called cyanogens, can be processed to remove the toxic substance. Cassava root has a very high cyanogen content and is used for tapioca and other food stuffs. Proper processing of cassava and thorough cooking renders the cyanogen harmless. The toxins in almonds also are processed in such a way to either remove the toxin or convert it into a harmless substance.

How Cyanide Acts

Hydrogen cyanide, the form of toxin produced by amygdalin conversion in the intestine, acts by robbing the blood cells of the ability to carry oxygen. While the body can process and eliminate small amounts of hydrogen cyanide, larger amounts can be deadly. There is no antidote.

Symptoms of Poisoning

Persons who experience apple seed poisoning may have trembling, spasms, dizziness, nausea, vomiting, restlessness, rapid heart rate, weakness and headache. Large amounts of cyanide can cause difficulty breathing, coma, respiratory failure, low blood pressure, convulsions, lung damage or death. Survivors of serious poisoning can show evidence of heart and brain damage.

The Good News

Handling apple seeds properly will prevent toxicity.