I Swallowed A Cherry Pit! Are Stone Fruit Pits Poisonous?

The Bottom Line

Although the seeds of stone fruits naturally contain cyanide, small unintentional ingestions generally do not cause harm. However, swallowing, crushing, or chewing the seeds should be avoided. Ingesting stone fruit pits, kernels, or seeds as complementary or alternative medicine is unsupported by scientific evidence and is dangerous and possibly deadly.

The Full Story

You're sipping on your delicious post-workout smoothie when you swallow something hard. You realize you unintentionally threw in some whole cherries without removing the pits and now you've swallowed some. You search the internet and are shocked to learn that you might have just swallowed one of the deadliest poisons known to man – cyanide. Oh no!

Rest assured that a small unintentional ingestion of cherry pits will not cause harm. But is it true that there is cyanide in cherry pits? What about other kinds of stone fruits? Can someone really become poisoned by eating them?

A stone fruit, also known as a drupe, generally refers to the Prunus family. Apricots, cherries, plums, peaches, mangoes, and nectarines are examples of stone fruits. In the center of the fleshy edible part of the fruit is a hard stone-like shell, which is the reason for their common name, "stone fruits". This hard shell is also often referred to as a pit or kernel. People might think that this "stone" is the fruit's seed, but this is incorrect. The seed is encapsulated within the shell.

The stone serves to protect the fruit and spread its seeds. This is the fruit's natural survival mechanism. Animals attracted to the fleshy, sweet, edible part of the fruit eat it and leave the hard indigestible pit behind. Or if the fruit is swallowed whole, the pit and the seed inside pass through the gastrointestinal tract and in the stool, intact and unharmed, returning back to the soil.

The dangerous chemical found in the seeds of stone fruits is called amygdalin. Poisoning can occur when the pit and seed are crushed or chewed before swallowing, releasing the amygdalin. Amygdalin is then converted by the body to cyanide. Many other types of plants found in the US, both edible and nonedible, also naturally contain cyanide compounds. These include cassava, lima beans, apple, Hydrangea, and bitter almonds.

The amount of amygdalin in the seeds of stone fruits varies widely, both between different types of stone fruits (e.g., cherries vs. plums) and even within the same type of fruit (e.g., cherries from one tree vs. cherries from another tree or geographic location). This makes it difficult to determine the number of seeds it takes for poisoning to occur. In general, unintentional ingestions do not lead to poisoning because it is unlikely that someone would chew or crush the kernels/seeds prior to swallowing them, and because unintentional ingestions tend to be of small amounts.

Cyanide's reputation for being deadly is well-deserved and has to do with the way it poisons the body. Cyanide poisons the most basic and fundamental units of life – the cells – by depriving them of the oxygen needed for life. While symptoms can vary depending on the amount of cyanide the body is exposed to, large exposures can quickly lead to loss of consciousness, acid buildup in body fluids, seizures, sudden loss of blood flow to vital organs, and death.

A drug called Laetrile, a chemical that comes from amygdalin found in stone fruit seeds, gained popularity in the 1970s as a treatment for cancer despite no evidence to support this claim. It was even marketed as a new vitamin "vitamin B17". Subsequently, health-food stores began to sell apricot kernels for their natural amygdalin content and its claimed anticancer benefits. As a result, several cyanide poisonings from ingestion of large amounts of apricot kernels occurred in the US. Scientific studies have shown that Laetrile has no anticancer activity in humans, and it has since lost much of its popularity. However, there are still some apricot kernel products being sold, especially on the internet, with the same claims about the benefits of "vitamin B17".

Although unintentional ingestion of a few stone fruit pits is typically not a concern, prevention is key; ingestion should always be avoided and the pits should never be crushed or chewed. Children should be taught to spit out the seeds/pits when snacking on stone fruits.

If you have any questions about stone fruits or if someone has ingested the pits, kernels, or seeds, check the webPOISONCONTROL® online tool or call Poison Control at 1-800-222-1222 for guidance.

Serkalem Mekonnen, RN, BSN, MPH
Certified Specialist in Poison Information


For More Information

Poisonous and non-poisonous plants: an illustrated list. Washington DC: National Capital Poison Center [accessed 29 Nov 2018].

Public health statement: cyanide. Atlanta: Agency for Toxic Substances and Disease Registry; Jul 2006 [accessed 29 Nov 2018].


References

Akil M, Kaya A, Ustyol L, Aktar F, Akbayram S. Acute cyanide intoxication due to apricot seed ingestion. J Emerg Med 2013;44:e285-6.

Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment. Statement on cyanogenic glycosides in bitter apricot kernels. Dec 2006. [accessed 28 Nov 2018].

Crisosto CH, Day KR Stone fruit. In: Rees D, Farrell G, Orchard J, editors. Crop post-harvest: science and technology: perishables. Chichester, Sussex UK: Blackwell; 2012. p. 212-25.

Drupe. New World Encyclopedia. 21 Nov 2008 [accessed 28 Nov 2018].

FDA cracks down on laetrile resurgence. New York: ABC News. 7 Sep 2018 [Accessed 28 Nov. 2018].

Geller R, Barthold C, Saiers J, Hall A. Pediatric cyanide poisoning: causes, manifestations, management, and unmet needs. Pediatrics 2006;118:2146-58.

Herbert V. Laetrile: the cult of cyanide. Promoting poison for profit. Am J Clin Nutr 1979;32:1121-58.

PDQ Integrative, Alternative, and Complementary Therapies Editorial Board. Laetrile/amygdalin (PDQ). Bethesda MD: National Cancer Institute; 15 Nov 2017 [accessed 28 Nov 2018].

Sauer H, Wollny C, Oster I, Tutdibi E, Gortner L, Gottschling S, et al. Severe cyanide poisoning from an alternative medicine treatment with amygdalin and apricot kernels in a 4-year-old child. Wien Med Wochenschr 2015;165:185-8.

Soloneski S, Larramendy M. Toxicology - new aspects to this scientific conundrum . Rijeka, Croatia: InTech. P. 179-91.

Suchard J, Wallace K, Gerkin R. Acute cyanide toxicity caused by apricot kernel ingestion. Ann Emerg Med 1998;32:742-4. 

Poisoned?

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Prevention Tips

  • Avoid swallowing stone fruit pits, kernels, or seeds. Teach children to spit them out.
  • Do not chew or crush fruit pits, kernels, or seeds prior to consumption.
  • Remove the pits of stone fruits before placing them in a blender.
  • Do not consume stone fruit pits, kernels, or seeds for their claimed health benefits.

This Really Happened

A 41-year-old woman purchased apricot kernels from a health food store. She then chewed and swallowed up to 30 of them. Within minutes, she became gravely ill. She felt weak, short of breath, numb, and had difficulty swallowing. A friend called 911.

When the ambulance arrived, EMTs found her on the bathroom floor moaning, sweaty, and barely responsive. Her skin was pale and her blood pressure was low. They treated her with oxygen and an intravenous medication to increase her blood pressure and transported her to a hospital. In the ER, she was found to be in an acidic state (the pH of her blood was very low). This is a classic sign of cyanide poisoning.

After hearing that the woman had chewed and swallowed a large quantity of apricot kernels, the ER physician recognized cyanide poisoning right away and immediately began treating her with the antidote for cyanide. She improved after 24 hours of treatment in the intensive care unit and was able to go home without any complications a day later.

(from Suchard et al. 1998)