There are plenty of myths floating around about watermelon seeds. Are the white ones actually safer to eat than the black ones? Should you only go for seedless watermelons? And sure, you’ve probably heard that swallowing black seeds won’t make a watermelon grow in your stomach—but are there any real health reasons to steer clear of them?
Here’s the deal: If you happen to swallow a few watermelon seeds, you’ll be just fine. In fact, you might even get some health perks.
Toby Amidor, RD, author of Up Your Veggies: Flexitarian Recipes for the Whole Family, told Verywell that the white “seeds” in seedless watermelons are actually empty seed coats where a seed didn’t fully develop—and they’re totally safe to eat. As for the black seeds in regular watermelons? Those are mature, fertile seeds that could grow into a watermelon plant if planted. But don’t worry—they’re safe to eat too. They’re insoluble fiber, so they’ll just pass right through your system.
Other good sources of soluble fiber include black beans, Brussels sprouts, and avocados.
For most people, swallowing any kind of watermelon seed is perfectly safe and even healthy. These little seeds pack nutrients like iron, folate, and niacin.
Kacie Barnes, MCN, RDN, a Dallas-based dietitian, told Verywell, “While they’re not exactly tasty on their own, watermelon seeds can actually give your nutrition a nice little boost.”
Some people get creative by turning them into seed butter, flour, or just roasting them to add to their diet.
That said, Amidor warns that if you have a sensitive stomach, eating watermelon seeds might cause constipation or some digestive discomfort.
Too many seeds can give you a big fiber hit, which might upset your digestion if your body isn’t used to it. But there’s no official limit on how many watermelon seeds are safe to eat.
Which Seeds and Pits Should You Avoid?
It’s a relief to know you don’t have to pick out every single watermelon seed. But that doesn’t mean you should go around eating every seed or pit in your fruits and veggies.
Amidor points out that some seeds are perfectly safe, like:
- Cucumber seeds
- Pomegranate seeds
- Dragonfruit seeds
But others can be harmful if eaten in large amounts.
Cherry Pits
These contain prussic acid (aka cyanide), which is poisonous. Swallowing one or two whole pits likely won’t hurt you—they’ll just pass through. But crushing or chewing them is a bad idea, since that releases the cyanide. (If you’ve seen Ozark, you know how that can go. Poor Jacob Snell.)
Apple Seeds
These also have cyanide. Swallowing a few whole seeds isn’t a big deal—their tough coating keeps the toxin sealed inside. But chewing or crushing too many could be risky.
Apricot Seeds
Found inside the pit, these contain cyanide too. Eating them can cause stomach pain and illness, and they’re especially dangerous for kids. In fact, some studies show that apricot seed poisoning in children can be so severe that many need intensive care.
Red Kidney Beans
Okay, they’re not seeds or pits, but they’re worth mentioning because raw or undercooked red kidney beans contain a toxin called phytohemagglutinin. Raw ones have 20,000 to 70,000 toxic units (hau), while fully cooked ones drop to just 200–400 hau.
White kidney beans have about a third of the toxin compared to red ones.
Amidor notes that as few as four or five raw or soaked red kidney beans can cause toxicity in just one to three hours, leading to nausea, vomiting, diarrhea, and stomach pain.
What This Means for You
Fruits, veggies, and beans are great for a balanced diet, and eating more of them is usually a good thing. But some seeds, pits, and raw foods come with surprising risks. From apple seeds to cherry pits, being careful not to crush or swallow certain ones can help keep you safe.
Luckily for watermelon lovers, those little seeds are totally fine for most people.