The Scientific Reason Pineapple Burns Your Tongue When You Eat It

Digging into some juicy pineapple is one of my favorite summer pastimes. I’d like to eat an entire bowl of it—and then go back for another serving and maybe even a third. What’s holding me back? I mostly limit myself because anytime I devour the tangy fruit, it triggers the most annoying stinging sensation on my tongue.

And I know I’m not alone; I’ve come across countless videos of people sharing similar tingly experiences. Most often, they blame a pesky enzyme in pineapple as the main cause of all that suffering. But recently I stumbled across another possibility: A TikTok claiming that tiny, irritating shards found in the fruit’s flesh are actually the real culprit.

Shocking, right? I was skeptical, since you obviously can’t believe everything you see online. So I decided to connect with an expert to figure out what’s really happening—and if there’s a way I can live out my pineapple-eating dreams annoyance-free.

First of all, does pineapple really contain tiny shards?

Figuring out whether this is true or not was my first order of business, because, well, the thought of eating sharp fragments is pretty alarming.

Turns out, it is true, but it’s not as dramatic as it sounds. The “spikes” in question are called raphides. They’re sharp needle-like crystals made of the mineral calcium oxalate (the same substance that forms kidney stones) that serve as the fruit’s natural defense of sorts, Michael P. Sheehan, PhD, an adjunct clinical assistant professor of dermatology who specializes in plant irritant allergies at Indiana University School of Medicine, tells SELF. Pineapples can’t just run away anytime a predator (okay, me) tries to prey on them, so over time they developed a protective mechanism that triggers an expulsion of pricks, Dr. Sheehan says.

Other produce like kiwis, spinach, and rhubarb also have raphides, which may explain why some people feel a similar irritation after eating them too.

The good news is, those spikes are so microscopic that you can only see them under special equipment. That means they’re not hearty enough to inflict serious harm to a human mouth, but they can do some damage to insects like baby moths. It still doesn’t mean people are in the clear, though. Raphides can cause microscopic abrasions to tongues and the insides of cheeks, Dr. Sheenan says. Then, when the tangy, acidic juice from the pineapple seeps into those tiny microabrasions, you feel that tingly, burning sensation.

So what about that enzyme?

Okay, the tiny shards theory checks out. Does that mean the tingly enzyme hypothesis is bogus?

Nope. Bromelain—an enzyme found in pineapple that helps disintegrate protein—also plays a role in irritating your tongue, Dr. Sheehan says. Your mouth can’t handle the chemical as well as your GI tract can: Bromelain breaks down proteins that are part of the mucus lining on your cheek, which wears away at the protective barrier. This allows the acidity from the pineapple to get in and cause an annoying tingly sensation.