Are You a Mosquito Magnet? Some People Are 100 Times More Attractive to Mosquitoes Than Others, New Study Reveals
The key is in your scent.
Mosquitoes are the bane of the warmer seasons. Their bites can range from annoying to dangerous—some mosquitoes carry viruses such as West Nile—and millions of dollars are spent each year to repel or eliminate them, with limited success. But science may be able to aid that nagging pursuit: Some people claim mosquitoes are particularly drawn to them, and a new study says those people may be right.
"The question of why some people are more attractive to mosquitoes than others—that's the question that everybody asks you," said Leslie Vosshall, a neurobiologist and mosquito expert, in Scientific American. "My mother, my sister, people in the street, my colleagues—everybody wants to know."
Published this week in the journal Cell, the study found that a person's body odor can make them more or less appealing to mosquitoes. And that tends not to change over time, despite variations in diet or grooming habits. Read on to find out what the scientists found—and how you can use it to make yourself less attractive to the bloodsuckers.
Scientists have been scratching their heads for a while about why mosquitoes are more attracted to some of us than others. An early theory—blood type—wasn't corroborated by data. Eventually, researchers decided it had to do with body odor but haven't been able to isolate exactly what specific odors are appealing to mosquitoes.
Every person has a unique scent profile comprising many different chemical compounds. In the Cell study, Vosshall and her team of researchers found that mosquitoes were attracted to people whose skin produces high levels of carboxylic acids—and that tends not to shift when lifestyle changes are made.
In the study, researchers asked 64 people to wear nylon stockings on their arms for six hours, suffusing the material with each person's scent. The researchers then cut the nylons into pieces and placed samples from two participants into a box containing female mosquitoes.
Then the scientists recorded which samples were most enticing. One study participant, #33, was a major mosquito magnet—mosquitoes' attraction to their sample was "over 100 times greater" than to the least attractive subjects.
Researchers analyzed the participants' scent profiles to explain this disparity. They found that the skin of the most attractive subjects produced higher levels of carboxylic acids, while less attractive subjects produced much lower ones.
Scientific American explains that carboxylic acids are common organic compounds produced by humans in sebum, the oily layer that coats our skin. It helps keep our skin moisturized and protected.
So what is it about carboxylic acids that's so appealing to mosquitoes? The sebum produced by our skin is consumed by the millions of good bacteria that colonize our skin to produce more carboxylic acid. In large amounts, the acid can produce an odor that smells like cheese or smelly feet, Vosshall told the Washington Post. That smell appears to attract female mosquitoes, who consume human blood to obtain the protein they need to reproduce. It's not clear why some people produce more carboxylic acid than others.
But what scientists know is that we retain about the same level of carboxylic acid in our skin over time—regardless of whether we're experimenting with vegetarianism or trying a new soap. "This property of being a mosquito magnet sticks with you for your whole life—which is either good news or bad news, depending on who you are," Vosshall told Scientific American. The good news for everyone: The study's findings may help scientists develop more effective mosquito repellants in the future.
LJ Zwiebel, a professor at Vanderbilt University who wasn't involved in the study, told the Washington Post that while carboxylic acids clearly come into play in mosquito-human attraction, no one compound attracts mosquitoes. He said a cocktail of natural chemicals are probably responsible.
The news you can use: If you don't want to get bitten by mosquitoes, Zwiebel advised taking a shower to reduce "all these juicy compounds" on your skin, especially around your feet, with its "unique odors."