Where Do Fruit Flies Lay Eggs And What Happens When You Eat Them?

You're sitting at home in your favorite chair, scrolling through your social media feed. From the corner of your eye, you notice something small and black darting around, near your face. You stop for a moment, chalking it up to eye strain from too much gadget use. But it only takes a few seconds for you to realize that you're actually dealing with a fast-flying, pint-sized annoyance — one that can quickly multiply inside your house, if you don't do anything about it.

Fruit flies (Drosophila melanogaster) are the bane of many a housekeeper or restaurant staffer. Tiny enough to be tough to kill and oftentimes a persistent problem because of their impressive reproductive capabilities (up to 500 eggs at a time), these unwelcome house guests go by such unflattering names as banana flies, vinegar flies, vinegar gnats, and sour flies. 

But those not-so-nice nicknames offer a clue as to where these potential disease-carriers like to hang out and lay eggs. Fruit flies love decaying, rotting, or pungent smells, and are thus attracted to fruits and vegetables that are already going bad. Such food items serve as both a nesting place and a food source for newly hatched fruit fly maggots. Oh, and if you have a habit of leaving uncovered glasses of juice or wine, beer bottles, or vinegar containers around the house, you're bound to attract these pests, too.

Many cooking and baking enthusiasts have found ways to repurpose otherwise unappetizing food items as ingredients. But now that you know that such foods are fruit fly favorites, a new question might be floating around in your head: What happens if you ingest a fruit or vegetable that already has (ick) fruit fly eggs in it? Is it safe to eat overripe bananas and other fruits?

As repulsive as the notion undeniably is, at the very least, it's not an instantly life-threatening predicament. Realistically, you can expect the typical symptoms that one would experience from eating nasty food, such as nausea, vomiting, and abdominal pain. A bacterial infection or allergic reaction is also possible, both of which can be dangerous. A particularly perilous, but rare, possibility is myiasis — when fruit fly eggs survive your digestive acids long enough to hatch into larvae, take up residence inside your body, and start eating your organ tissue, which may bring abdominal pain, diarrhea, and vomiting.

With that said, timely medical intervention can help you bounce back quickly and prevent further complications, so seek medical attention as soon as you suspect that something's off with the food you just ate.

The best way to prevent the accidental consumption of fruit fly eggs is, of course, to prevent fruit flies from multiplying in your home in the first place. Avoid leaving food and drinks uncovered for long periods of time, and keep your kitchen and bathroom drains clean and unclogged (because fruit flies love the food particles and/or residue stuck in those, too).

Also, pay attention to tell-tale signs that certain foods aren't safe to eat, so that you can remove them from your home and prevent them from becoming a hotspot for fruit flies. (By the way, here's a list of foods you should never eat past their expiration date.) Additionally, make it a habit to regularly and promptly take out the trash.

Lastly, if you find that there's already a fruit fly problem in your home, don't fret. A simple and time-tested (albeit unpleasant-smelling) DIY solution would be to fill a jar or cup with apple cider vinegar or water with yeast and a dash of sugar, cover it with a plastic lid with tiny toothpick-sized holes, and leave it where you want to attract the fruit flies. The smell will draw them in, but they won't be able to get out, and they (and whatever eggs they end up laying) will spend the rest of their short lives trapped until they (literally) drop like flies.