Before you bite into an apple or sprinkle some berries on your cereal, you most likely give the fruit a good rinse. When it comes to bananas, however, you probably skip this step. After all, their peel is nature’s version of a screen protector—right?
If your banana has never known the kitchen sink, you might be surprised to see some TikToks encouraging people to wash the fruit post-purchase. The videos claim that fruit flies lay eggs on top of bananas, potentially causing that swarm in your kitchen, no matter the season. So: Should you rinse those potassium powerhouses to keep your kitchen tidy? We connected with several entomologists to find out.
First of all, it turns out the fruit fly infestation part is legit. While bananas aren’t inherently more attractive to the insects than other types of fruit, they do have a couple characteristics that make them particularly vulnerable, David Lowenstein, MS, PhD, a consumer horticulture educator at Michigan State University Extension, tells SELF. For one, they’re more likely to be stored outside of a temperature-controlled environment like the fridge, making it easier for the flies to access them. Second, they ripen more rapidly, meaning they start to attract pests earlier as decay sets in.
And those bananas aren’t just a food source for the insects; they also serve as an excellent nursery for their babies, which are actually at the root of the swarm problem here. Within around 24 hours of mating, female fruit flies can lay as many as 500 tiny eggs on surfaces like a banana’s peel. “You would need a good hand lens or a microscope” to see them, Dr. Lowenstein says.
But when those eggs hatch, they produce larvae (a.k.a. maggots), which, in turn, become brown, oblong pupae that will eventually yield adult flies. If this cycle completes, you could have a big problem on your hands. “Once you get just a few fruit flies inside, their populations can explode really quickly,” hence any potential swarms, PJ Liesch, MS, the director of the University of Wisconsin-Madison Insect Diagnostic Lab, tells SELF. In fact, he adds, “you can even get overlapping generations, where you might have adults and eggs or larvae at the same time.”
Due to the small size of the eggs, you’re not going to be able to distinguish between bananas that carry them and those that don’t—so anytime you purchase a bunch, it’s “certainly within the realm of possibility” that you could be buying these pests along with it, Liesch says.
So yes, those TikToks weren’t too far off: Your fruit fly problem may stem from any bananas (or other fruit) you have sitting around.
Of course, not every single banana at your local grocery necessarily harbors fruit fly eggs—it’s more likely if you actively see adults buzzing around in the produce section, according to Dr. Lowenstein. And even if some stowaways do slip on board, you won’t be in danger of eating the eggs (or, maybe even grosser, the maggots), since they’d be on the banana peel rather than the fruit itself. (Unless there’s a break in the peel; in that case, the eggs and the larvae could get inside. But even then, the worst that could happen is that “you’re getting a really small amount of protein,” Dr. Lowenstein says—it’s not going to make you sick.)
Still, if you’d rather keep fly eggs from multiplying in your kitchen, you might be wondering if the social media videos encouraging washing bananas are onto something. Sort of: Sure, it’ll “remove the eggs,” Dr. Lowenstein says. (Fruit and vegetable washes are okay, just don’t use any soap or detergent.) But it also honestly might not be worth the trouble—especially if you’re a big banana fan.
That’s because growth and development takes time, even for fruit flies. While the length of this process can vary depending on the ambient temperature—for example, warm weather speeds it up, and cold weather slows it down—it tends to be “in the range of about a week or so,” Liesch says. So, assuming you’re eating your bananas within four to five days of purchase, “the odds of getting adults that came from eggs would be pretty slim,” he adds. (If your banana bunch has been infiltrated by pupae versus eggs, though, that may be another story: They could potentially produce adult flies “pretty much right away,” Liesch says.)
Another reason you don’t want your fruit to hang around too long: Hatching larvae eat “damp, decomposing, organic matter,” Liesch says—think aging or damaged produce—so if your bananas are gone before they start to go bad, poof goes the food source for those babies.
Basically, washing your bananas shouldn’t be necessary if you eat them sooner rather than later. “It’s just probably an extra step that you don’t really need to do,” Dr. Lowenstein says.
What matters more for avoiding the swarm? “The best thing you can do is prevention,” Dr. Lowenstein says—namely, staying on top of regular household cleaning to suppress conditions fruit flies might find extra attractive. For instance: Clean up spills and toss out food scraps promptly. Make sure you check spots you might normally overlook, like the bottom drawer of the fridge, the lip of the sink, and tiny nooks and crannies in your pantry. Use produce sooner rather than later, and store what you can in the refrigerator. (Maybe not bananas, though: “They get kind of a funky texture,” Liesch says.)
And finally, don’t be misled by the name “fruit fly.” If you’re following all the tips above and are still dealing with the little buzzers, the “fruit” (or its debris) might not even be to blame. Plenty of times, another source—whether it be a gunk buildup in a drain, a subtle leak beneath the dishwasher, a damp patch of material in a garbage can, or a bag of potatoes in long-term storage—may be the culprit, Liesch says. And if the problem persists? Luring the flies to a quick, um, demise with a bowl of wine or apple cider vinegar should clear up your kitchen airspace in no time, according to Dr. Lowenstein.
Related:
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- Are Those Squiggly White Things in Your Berries Actually Worms?
- How to Actually Protect Yourself Against Mosquito Bites
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