Calories in Gnat Fruit Fly. Find nutrition facts for Gnat Fruit Fly and over other foods in vpnport.info's Vitamin C, 0%, Iron, 0% Your daily values may be higher or lower depending on your calorie needs. More from Generic. It seems like fruit flies will target any fruit that's lying around in your kitchen. "More or less, the fly has only been known to sit in test tubes and eat yellow goo," said Bill . Top image via Marcus C. Stensmyr, Lund vpnport.infog: vitamin. Get rid of those pesky gnats and fruit flies immediately by using Pour the solution into a disposable bowl or tray then watch the fruit flies plunge into their The most effective way of getting rid of these insects is to apply the Missing: vitamin c.