Are Mosquitoes Gender Biased?

The Claim: Mosquitoes are attracted to women more than to men.

The Facts: Mosquitoes find some people tastier than others. But a widespread notion is that women, to mosquitoes at least, are the sweeter sex, supposedly because oestrogen is a strong attractant.

In reality, gender does play a role, but not in the way most people think. As one report in the Annals of Internal Medicine pointed out, men are more likely to be attacked, primarily because of their greater body size.

“Larger persons tend to attract more mosquitoes perhaps because they emit greater relative heat or carbon dioxide,” the study said.

A similar effect can be seen among women. When scientists compared pregnant women with their non-pregnant counterparts in a Lancet study in 2000, they found that the pregnant women attracted twice as many mosquitoes. The study noted that the pregnant women exhaled more carbon dioxide and had higher body temperatures, allowing mosquitoes to detect them more easily.

In addition to carbon dioxide, lactic acid is also a strong attractant, which is why people are attacked more when they are outdoors and sweating, said Dr. Clifford Bassett of Allergy and Asthma Care in New York. “Mosquitoes can sense these chemicals up to 30m away.” Dr Bassett said.

The bottom line: Research suggests that men are more likely than women to be attacked by mosquitoes.

- The New York Times