Do fruit flies eat more than fruit?

Do fruit flies eat more than fruit?

You see a swarm of fruit flies in your home, but wonder what they’re actually feasting on. Are they after more than just those bananas?

Fruit flies don’t technically eat, as their mouthparts cannot pierce a tough surface. A fruit fly has a tubular channel, with sponge-like lobes at the end, which is used for sucking or lapping up liquids. Like the common housefly, fruit flies secrete a viscous liquid as saliva, helping to turn their soon-to-be lunch into the liquid form that they relish. Basically, they vomit and then slurp that disgusting mixture up, now mixed with bits of banana or overripe cantaloupe. 

Can a fruit fly bite me?

One thing you don’t ever have to worry about: getting bit by a fruit fly or seeing your eight-week-old pup scratch incessantly from being attacked by fruit flies. It won’t happen. It’s biologically impossible. Note: If you have a tiny biting friend, it’s probably a gnat. These little pests usually cause small, red bumps that cause itching and irritation.

What exactly do fruit flies eat?

Now that we’re all too aware of how a fruit fly dines, let’s explore the types of food that they enjoy feasting on. A population of fruit flies feeds from a number of sources, including the secreted honeydew of aphids, fermenting sugar in alcoholic beverages, mushrooms, the sludge in the bottom of your garbage can, yeast, and the sap flow of plants, and the rotting bananas on your countertop, to name a few. Basically, fruit flies are attracted to sweet-smelling, sugary, and fermented scents. To be specific, they crave the carbon dioxide that is released when food is fermented.

Now for the details…


Honeydew secreted by aphids

Aphids eat a lot of plant sap and must discharge the excess sugar. This excess is eliminated through their anus. Fruit flies to the job! They will happily slurp up this (already digested) sugar.

Fermenting sugar in alcoholic beverages

A fruit fly’s personal preference would be to feast and then lay their eggs on spilled beverages containing ethanol. All alcoholic beverages contain ethanol, though the amount can vary.


Not all fruit flies adore mushrooms, but some species do. Just note that if you’re growing mushrooms, whether indoors or outdoors, they can be an ideal breeding ground for fruit flies.

Sludge in the bottom of your garbage can

Fruit flies like thick goopy textures. This sludge can best be described as the debris and liquid that collects in the bottom of your trash cans, in your garbage disposals, in your plumbing, and even in the seams of your appliances. Fruit flies don’t ask for much. Even a small amount of sludge can become breeding grounds.


Yeast makes fruity-smelling chemicals that allure fruit flies to their dinner. Be mindful of this the next time you’re baking bread or sprinkling brewer’s yeast on your salad. But, there is an exchange that happens here. The yeast hitches a ride on the fruit fly and then spreads their cells to new environments.

Sap flow of plants

Sap flow is the movement of fluid in the roots, stems, and branches of plants. Have you ever gone to a peach orchard, only to see dozens upon dozens of fruit flies hovering over rotten, fermenting peaches on the ground? They’re lapping up that sap flow in droves.

Rotting fruits and vegetables

The list includes bananas, melons, grapes, tomatoes, squash, apples, onions, and potatoes. It’s essentially any produce that you would potentially leave unrefrigerated. 

How does a fruit fly find its lunch? 


Using their pair of pill-shaped antennae, located on the front of its face, (in place of a proper nose), they smell out this fermenting food. It’s these antennae, with their highly specialized smelling nerves, that respond to particular chemicals and find the feaster’s lunch.

Final word on fruit flies

Fruit flies, with their specialized sniffing antennae, thoroughly enjoy fruit. But as you’ve learned, there are many foods that they will feast on. If you have fruit flies, know that they won’t go away on their own.

Keep your kitchen tidy, use Dr. Killigan’s Six Feet Under (a kill-on-contact non-toxic insect killer spray), cover that delicious fresh-out-of-the-oven bread, don’t forget about those bananas on your countertop, and remember that we have an amazing customer service team at 844-525-2779 if you ever run into a bug issue that you can’t solve. We can also be reached via chat on our website and through our contact form.

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