LITTLE ROCK, Ark. (KTHV) - Most of us will do anything to keep insects away during these hot summer months, including hanging Ziploc bags full of water, and sometimes pennies, on your patio.

Some swear it works to keep bugs away. But tonight, we verify if science can back it up.

Does hanging bags of water outside really keep insects away?

It's an old wives tale, but Dr. John Hopkins, an entomologist with the University of Arkansas Department of Agriculture answers if it really works.

"If people want them to work, let their imagination go," he said.

At Little Rock restaurant Ciao Baci, the owner hangs these water bags outside on the summer patio --and has for 17 years. She didn't want to speak on camera but believes there's at least some effectiveness.

Another woman, Cordelia Underwood, watched her grandparents do it when she was young.

"They would staple these bags of water to the cabin and it would keep the mosquitos out, but I don't think it ever actually worked," she said.

It turns out, there's little proof it actually does anything.

"There's no scientific evidence. In fact, there have been some studies that proved the other way," Dr. Hopkins said.

He referenced a 2007 North Carolina State University study, which showed that the use of plastic bags filled with water actually increased fly activity. He said the show Mythbusters also tested the idea and determined that the water bags weren't effective.

Still, many theories are abuzz as to why it might work. The most common is that the flies' complex eyes are overwhelmed by the refracted light produced by the bags, and so they fly away.

So, where do pennies fall in this theory?

"As far as the pennies go, you know people would probably be better served if they took those pennies, threw them in a wishing well and wished those flies away," Dr. Hopkins said.

So far, we can verify that while some people swear by them, there's no scientific evidence that hanging plastic bags filled with water will repel insects.