Why are some people mosquito magnets?

Written by Lisa Collier Cool

July 15th, 2013

 

If you feel as if every mosquito in a 50-mile radius has you locked in its sights, while your friends are rarely bitten, you could be right. Up to 20 percent of us are highly alluring to mosquitoes—and scientists have discovered some surprising reasons.

 

“Both your metabolism and your unique body chemistry—which is as distinctive as a fingerprint—play an important role in determining whether or not you’re a mosquito magnet,” says University of Florida entomology professor Dr. Phil Koehler. “Also, there’s evidence that your degree of attractiveness to mosquitoes can change over time.”

 

Here are some intriguing discoveries about why some of us are particularly tasty targets for the tiny vampires:

 

Mosquitos prefer blood type O

In their quest for a meal, mosquitoes are nearly twice as likely to land on people with type 0 blood than those with type A, according to a Japanese study.  Indeed, the biting pests consider type 0 more delectable than any other blood type, the researchers reported. Most people secrete substances that allow mosquitoes to identify blood type before they bite.

 

Beer drinkers beware

Swigging just one bottle of beer can significantly boost your risk of being bitten, according to a study published in Journal of the American Mosquito Control Association. The researchers reported that, “Mosquito landing on volunteers significantly increased after beer ingestion compared with before ingestion.”

 

Keep your socks on

The pungent aroma of dirty feet is apparently irresistible to mosquitoes, as a brave scientist, Bart Knols, discovered when he sat in a lab in his underwear to find out which parts of the body the pests are most likely to target. He found that 75 percent of the bugs homed in on his feet, but after he washed them with deodorant soap, the mosquitos bit randomly. His team also reported that stinky cheeses, such as Limburger—which has the same odoriferous compound responsible for foot odor—also draws mosquitoes.

 

Mosquitos know if you’re expecting

Moms-to-be get bitten about twice as often as women who aren’t pregnant, increasing their risk for bug-borne diseases, according to a study conducted in Gambia. The researchers hypothesized that since women in the later stages of pregnancy exhale 21 percent more volume, mosquitos were drawn in by the moisture and carbon dioxide in their breath. They also found that pregnant women's abdomens are nearly 1 degree warmer, which may cause more volatile substances—released in sweat and attractive to mosquitos—to be present on their skin. Not only do several other studies have similar findings, says Dr. Koehler, but “there’s also evidence that women are more attractive to mosquitoes during certain phases of the ovulation cycle.” Studies have mixed results as to whether men or women are more likely to get bitten, he adds.

 

Running won’t help you

Both the carbon dioxide we exhale and substances in sweat, such as lactic acid, help mosquitoes home in on their prey. As a result, Dr. Koehler reports. “You’re more likely to be bitten if you’re running or exercising than when you’re at rest, since you’re breathing harder and sweating more.” In fact, physical activity ups risk for bites by as much as 50 percent, according to AMCA.

 

Like vampires, they prefer dark clothes

Dark-colored clothing can increase your risk of falling victim to the little bloodsuckers, compared to lighter-colored garments, says Dr. Koehler. In one study comparing the appeal of various hues to mosquitoes, the researchers reported  the following results:  black (most attractive); red (very attractive); grey and blue (neutral); khaki, green, light khaki, and yellow (less attractive).

 

Watch out for the full moon

The tiny bloodsuckers are 500 times more active when the moon is full, reports the American Mosquito Control Association (AMCA). Overall, the highest risk times for mosquito bites are dusk and dawn, with the females of some species migrating up to 40 miles in pursuit of a meal. (Male mosquitoes don’t bite.)


 

[source: Day in Health Blog]