You probably remember this old wives’ tale from your childhood: If you eat the seeds of a watermelon, one of the large fruits will grow inside your belly.
Of course, it’s a total myth that’s simply funny to look back on now. Even if you buy seedless watermelon, it’s pretty much a given that you’re going to stumble across a crunchy black speck or two whenever you snack on the water-rich fruit.
But is it actually safe to eat watermelon seeds? Sure, you’re probably not sitting down and noshing on a whole bowl of them, but do they have any side effects that could stir up stomach troubles? Here’s what to know about the summer staple.
What happens if you eat watermelon seeds?
If you happen to eat a few seeds while working through a piece of watermelon, it’s really no big deal. “Watermelon seeds are safe to eat,” says Beth Warren, a registered dietitian.
“When eaten 100% raw—in other words, they still have the black shells on them—you do not digest them, but rather they pass through your body whole,” says Keri Gans, registered dietitian. So, they’ll just end up in the toilet in a day or two, similar to what happens when you swallow chewing gum.
That’s why, if you tend to have a sensitive digestive system, it’s possible to develop some stomach issues, like gas or bloating, if you eat too many of the seeds, says Jessica Cording, registered dietitian.
The seeds can also cause constipation. “It’s all about the amount you consume,” says Gina Keatley, a certified dietitian and nutritionist. “There is a good deal of insoluble fibre in the seeds, which can cause your digestive system to slow down if there is not enough water and other material to continue to push it through.”
However, if the seeds are sprouted or cooked, “your body digests them fully to reap the health benefits,” Gans says.
What are the benefits of watermelon seeds?
Turns out, watermelon seeds do have some nutritional value, but only when eaten in larger volumes since they’re so small.
“They’re a good source of magnesium,” a mineral that is involved in more that 600 chemical reactions in the body, Cording says. A 1-ounce serving of the seeds would give you about 30% of your daily magnesium needs.
The seeds even have some heart-healthy benefits, thanks to an antioxidant called lycopene, which gives red fruits and vegetables their vibrant pigment. The nutrient has “been linked to tons of positive health benefits, from cardiovascular health to cancer prevention,” Keatley says.
How to eat watermelon seeds
If you want to make use of some leftover watermelon seeds, toss them with a little olive oil and salt and stick them in the oven. “Watermelon seeds can be a great option for a healthy snack when roasted,” Warren says.
Those roasted seeds can also be a good way to add some crunch to salads, yoghurt, and oatmeal, Gans says.
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