Also Laetril or Vitamin B17
One of the ineffective pseudoscientific methods of alternative cancer treatment .
Amygdalin is a simple molecule - a cyanogenic glycoside consisting of two sugar residues and a small phenyl aglycon - occurring in bitter almonds, peach or apricot seeds. Amygdalin has a single function in plants: To be a source of poisonous cyanide, thus discouraging animals from eating seeds. In the second half of the 20th century, the idea was that hydrogen cyanide from amygdaline could be used to selectively kill cancer cells because they have somewhat higher metabolism than normal cells and are therefore more susceptible to cyanide. This idea is totally out of date, but the modified amygdalin has even been promoted under the names laetril and vitamin B17 to treat cancer.
To understand why amygdalin can not work against cancer , we need to realize that our cells have two ways to acquire energy: anaerobic (oxygen-free) and aerobic (internal breathing). Hydrogen cyanide blocks internal breathing, but the cell still has energy and anaerobic digestion of sugar. If we blocked the internal breathing of only a small number of body cells, they would easily survive through the supply of anaerobic energy from the rest of the body. Cyanide therefore has the ability to selectively kill only some cells at all - it kills the whole organism by the total exhaustion of energy. Hydrogen cyanide is therefore completely ineffective against cancer cells.