Are Apple Seeds Digestible?

Apple seeds are virtually indigestible.

Apple seeds are virtually indigestible.

Apple seeds, like many other seeds, contain small amounts of substances that are potentially toxic to your body if consumed in very large amounts. Most people avoid eating apple seeds because they aren’t particularly appetizing -- not because of profound fear of poisoning. The seeds are encased in tough fiber and are unlikely to be digested, so they pose little risk.

Apple Seeds

Apple seeds are the small, dark seeds that grow in all apples. Apples have five separate seed pockets or carpels. Each pocket contains seeds, although the number of seeds in each is determined by the growing conditions and health of the apple tree. In addition, different varieties of apples have different numbers of seeds. For example, red apples such as the Gala variety and some green apples such as the Granny Smith variety tend to have more seeds than yellow varieties.

Cyanogenic Glycosides

All apple seeds contain compounds called cyanogenic glycosides, which are molecules of cyanide attached to sugar. Amygdalin is such a compound, and it produces hydrogen cyanide when metabolized. Hydrogen cyanide is toxic because it reduces the ability of blood to carry oxygen to cells, so overdose victims essentially die of asphyxiation. However, each apple seed contains very small amounts of cyanide, which your body is easily able to neutralize. In fact, amygdalin in small amounts may provide some benefit because it’s able to kill pathogens in the bloodstream. You would need to eat handfuls of apple seeds for the risk of serious illness to become significant. Other fruits that contain cyanogenic glycosides in their seeds include peaches, apricots, cherries and raspberries. Bitter almonds are a particularly rich source of amygdalin.

Digestion of Apple Seeds

Consuming apple seeds and digesting them are two different processes. Most small seeds from apples and other fruits are accidentally swallowed or blended somewhat in a smoothie, which does very little to break them down. Apple seeds have tough protective coatings that allow them to pass through the digestive tract of most mammals intact, so unless you spend serious time chewing them or mechanically pulverizing them, very little of the amygdalin is likely to be released from the seeds and absorbed by your body. Being indigestible is a common characteristic of seeds because it allows them to be redistributed to new locations far from the originating tree. It’s simply a good reproduction strategy, and it happens to protect people from the toxic compounds.

Cautions

Although adults are unlikely to experience any ill effects from eating moderate amounts of apple seeds, your children or pets may be more susceptible because of their smaller sizes. Remove all seeds before you feed your children or pets apples, just to be extra safe. Symptoms of amygdalin toxicity may include severe stomach cramps, headache, dizziness, difficulty breathing and seizures. However, if a few too many seeds were to be eaten and partially digested, then you would likely vomit a few times and not develop more serious symptoms.

 

References

  • Textbook of Nutritional Medicine; Melvyn Werbach and Jeffery Moss
  • Principles and Practice of Phytotherapy: Modern Herbal Medicine; Simon Mills and Kerry Bone
  • American Cancer Society Complete Guide to Complementary and Alternative Cancer Therapies; American Cancer Society

About the Author

Sirah Dubois is currently a PhD student in food science after having completed her master's degree in nutrition at the University of Alberta. She has worked in private practice as a dietitian in Edmonton, Canada and her nutrition-related articles have appeared in The Edmonton Journal newspaper.

Photo Credits

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