Why Is It Considered Dangerous To Eat Apple Seeds?

You can easily find people who adore all varieties of apples, but you'd be hard pressed to find someone that eats the seeds. (Though even with all those unconsumed seeds, we've lost 17,000 different types of apples in North America alone due to agricultural progress.) Yes, the seeds can be dangerous, but with a few caveats. Apple seeds, like all fruits in the rosaceae family, produce seeds that contain amygdalin. Left totally alone, amygdalin probably won't do anything to you, which is why if you swallow whole apple seeds by accident, you'll be fine. And since we can't digest the outer layer of apple seeds, they'll just pass right through your digestive system, leaving you unharmed. 

However, if the apple seeds are crushed (please don't do this) and then consumed at the right amount, you're in danger. Amygdalin reacts to our digestive enzymes by releasing cyanide. It's like nature is screaming at us not to crush up and eat random seeds! But the key phrase is "at the right amount." The average lethal dose of ingesting cyanide is 1.5 milligrams per kilogram of weight, which puts the range of lethal doses at 50 to 300 milligrams. You would need to crush and then consume about 83 to 500 apple seeds to get acute cyanide poisoning. By contrast, you would only need to eat 50 bitter almonds (or 10, if you're a child) to die from cyanide poisoning, so you're safer all around with apples.

Cyanide poisoning from apple seeds is extremely unlikely, especially when you consider that each apple contains an average of three to four seeds  so you'd need about 20 to 125 apples to run into trouble. Of course, you'd also have to then core and then de-seed the apples ... and then crush up the seeds before eating them. I feel like there are more prudent ways to procure a poison, but hey, maybe I'm just lazy. Also, consider the fact that cyanide is used in a variety of industrial applications, including metallurgy, plastics, pesticides, photo development, dyes and mining. You're more likely to be exposed to it by working in any of those fields than a silly little apple seed. 

But this all leads to this point: You can actually just eat the whole apple. You'll live. You heard me right. Apple cores are a big food waste item, and some scientists and plenty of people have advocated for their consumption. Of course, in doing so, you may also eat a few seeds, but again, their protective layer keeps you from digesting them, and it would take upwards of 125 apples' worth of crushed seeds to cause any damage. So when you're munching your next apple, just eat the whole damn thing.