Mosquito Mythbusting: Will the Real Repellents Please Stand Up?

Scientists separate fact from fiction to help protect you from bug bites.

May 3, 2010, 4:42 PM

May 5, 2010 -- It's that time of year again.


barbecues, afternoon patio parties, outdoor lawn games -- and the irksome

insects that can spoil it all.

When the

mosquito wars begin, anything can look like a weapon to itchy outdoor enthusiasts. But experts say many home remedies are mostly sizzle and little substance.

To separate

mosquito fact from fiction, spoke to several scientists. Take a look at what they had to say.

Garlic: Is there an old wives' tale that doesn't feature garlic? According to lore, the pungent-smelling plant can do everything from cure the common cold to help determine a baby's sex to ward off witches.

But though some believe garlic has powerful bug-repellent properties, mosquito control experts say it isn't very strong.

"Garlic is a classic," said Joe Conlon, technical advisor for the American Mosquito Control Association. Some think that eating garlic could keep mosquitoes away, but he said studies have not shown that ingesting garlic reduces bug bites.

"As in most myths though, there is an element of truth in them," he said. "If you take garlic and squeeze it on your skin, that portion of your skin will be repellent to mosquitoes for about 20-40 minutes."

But, then again, he added, you'd be repellent to most everything else too.

Vitamin B: Can vitamin B tablets make you a less tasty treat to the biting menaces? Probably not.

Though some people swear by it, Conlon said that in double-blind studies, the vitamin continues to come up short.

When researchers at the University of Wisconsin asked volunteers to take placebos or capsules with vitamin B, they did not find any evidence that the substance could help reduce mosquito attraction.

Bananas: This one goes both ways. Susan Paskewitz, an entomologist at the University of Wisconsin at Madison, said that some people think the fruit attracts mosquitoes, others think it repels them.

But "the predominant thinking is that bananas do make you more attractive," she said. However, she said a study in her lab didn't prove a link between bananas and mosquito attraction.

"Some subsets of people show dramatic variability," she said, adding that whether people ate bananas or not, they might attract several mosquitoes at one time, and fewer mosquitoes hours later.

Can Some Household Products Double as Mosquito Killers?

Listerine: If the Internet is to be believed, this antiseptic mouthwash doubles as an effective bug repellent. But Paskewitz said that though some of the product's ingredients have been shown to be repellent, Listerine itself has yet to prove its power to science.

Conlon also said that the claim that the mouthwash fights mosquitoes has "no basis in fact."

Dryer Sheets: Some think this household product also moonlights in pest control, but Paskewitz said its properties have yet to be tested in the lab.

She said some might think that the strong-smelling compounds might make the person more or less attractive to mosquitoes, but she said she didn't think anyone had ever done a scientific study to examine a connection.

"If it worked, I would be completely amazed," she said.

Lemon Joy: Some think Lemon Joy, the dishwashing detergent, is another mosquito murderer in disguise. The idea, Conlon said, is that a few drops in a bowl of water will attract the bugs to lay eggs in the water and then kill them off.

But he said that, as with the other household products, no scientific proof supports this claim.

Alcohol: Believe it or not, there might actually be some truth to the claim that alcohol affects your attractiveness to bugs. Paskewitz said a couple of studies have shown that drinking beer could make a person more attractive to mosquitoes.

"There's possibly something different about the way they smell to a mosquito" or a change in temperature, she said.

Conlon said alcohol could play a role because people who sweat a lot tend to attract mosquitoes and drinking could make someone flush and their skin become a little warmer.

If you really want to protect yourself from mosquito bites, Conlon suggested following the three "D's": Drain, dress properly and defend.

First off, he said, "Drain any standing water around the house."

Mosquitoes will breed in whatever is accessible to them, so he said to empty flower pots and air conditioner unit drain pans and even make sure water isn't trapped in the folds of tarps covering woodpiles or backyard equipment.

It takes mosquitoes from five to 14 days to grow from egg to adult, so he suggested draining every five days.

He also said it's important to dress properly.

Expert: Drain, Dress Properly and Defend

"Mosquitoes can and will bite through tight-fitting clothing," he said, so loose-fitting clothing of a light color is preferable. He also said to wear long sleeves and pants if you're in an a particularly mosquito-infested place.

Finally, he said that people should defend using a known mosquito repellent.

The "gold standard," he said is DEET, which should be applied directly to the skin, while keeping it away from eyes, ears and mouth.

"Any place on your body that's exposed is fair game," he said. So "you've got to be thorough."

Picaridin is another effective DEET alternative and is popular because it's lighter and barely smells, he said.

"Outside of the U.S., it's the largest selling repellent in the world," he said.

And for those who want a natural repellent, he suggested oil of lemon eucalyptus, which has been recommended by the Centers for Disease Control.