|MadSci Network: Biochemistry|
Dear Julie & Karine,
These are very interesting questions.
First, can Laurel's leaves tea ease a throatache?
Laurel's leaves tea is prepared from a plant having the botanical name of Laurus Nobilus. The common names for the plant are Bay, Sweet Bay, Bay Laurel, True laurel, Noble Laurel, Roman Laurel, Indian Bay. You may know it as Bay leaves, which are used in cooking soups and meats. It has been claimed to be useful for treating chest colds and to aid digestion. However, I am not aware of any scientific studies that have confirmed these claims.
Second, do Laurel's leaves contain cyanide?
The leaves of Laurus Nobilus contain little, if any, cyanide. HOWEVER, there are several related plants, also called Laurel, that do contain cyanide and other poisons. For example, the leaves and berries of Cherry Laurel (Prunus caroliniana laurocerasus) contain a chemical known as amygdalin, which is broken down to release cyanide (see below). Mountain Laurel (Kalmia latifolia) contains chemicals called andromedotoxin (grayanotoxin) asebotoxin and arbutin, which are toxic. Kalmia augusfifolia (Sheep's Laurel) and Kalmia glauca, (Swamp Laurel) are related to Mountain laurel. These plants are poisonous, causing stomach and intestinal irritation, paralysis, convulsions and may be fatal.
For information on other types of Laurel plants and their toxic effects, see these web sites:
Third, does cyanide have positive effects and, if so, what are they and why
doesn't a person die when he/she ingests it?
There have been claims that cyanide in small amounts does have "beneficial" effects. Before I tell you what these claims are, I want to note that this is a very controversial area. Also, you should know that people differ in their response to a given dose (amount) of any chemical (medication, toxin, etc) and, therefore, the amount of a chemical, such as cyanide, that may be "beneficial" for one person could be toxic for another person. Clearly, the risks associated with the use of cyanide are great. Now that I've cautioned you, there is some evidence that amygdalin, which is present in many types of Laurels, and which is broken down in the body to release cyanide may be useful in treatment of certain types of cancer. See:
Also, I have heard claims that cyanide improves digestion. I can not say whether these claims are true or false. However, I know of no medical evidence that support them.
Finally, note that cyanide in a component of vitamin B12 (cyanocobalamine), which is required in minute amounts in the diet.
I strongly urge you to consult with a physician before you take any herbal remedy. Do not be afraid to ask questions.
I hope that this information is useful
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