A house fly will regurgitate digestive juices onto solid foods and these juices break down the food into small pieces, allowing them to use their mouthparts, called proboscis, to drink the meal.

Do flies drink sugar water?

Fill the bottom part of the bottle with a quarter cup (60 mL) of sugar, a quarter cup (60 mL) of water, and a couple of drops of blue food colouring. The blue colour helps to attract flies, but most colours or no colours will attract flies as long as it isn’t yellow.

What do I feed a fly?

Feed your fly foods high in sugar. Flies will eat almost anything, but they especially love sugar, and liquids are preferable, though they can make foods liquid to drink. You can try bits of fruit (except citrus), syrup, and even straight sugar.