Have you ever attended a friend’s outdoor barbecue and wondered, “Why do mosquitoes only bite me?” (If so, you’re probably dreading any upcoming Labor Day shindigs, which might require spending hours in the sun being eaten alive by these pesky bloodsuckers.) It appears as though some species of mosquitoes exhibit a preference when it comes to their next meal, so no, you’re not imagining things — some people really are more likely to get bitten by a mosquito than others.
So, why can some people get away with leaving without a single bite while you scratch yourself raw despite showering in bug spray? There are plenty of old wives’ tales that supposedly explain mosquito behavior, like the idea that eating bananas will attract hungry mosquitoes. However, the real reason is a lot more complicated.
Researchers aren’t sure exactly why certain people are mosquito magnets — according to University of Florida professor Jonathan Day, 20 percent of all people fall into the category of “high-attractors” — but they believe it may be due to a variety of factors, both biological and physical.
In a July 2004 study published in the Journal of Medical Entomology, mosquitoes were significantly more likely to land on people with type O blood (83.3 percent) compared to people with type A blood (46.5 percent), while type B blood was somewhere in the middle. In addition to blood type, whether someone was a secreter (meaning they release a chemical through their skin that indicates their blood type) was found to be a deciding factor. As it turns out, it appears secreters are more likely to have a mosquito land on them regardless of blood type.
Carbon dioxide is an indicator to mosquitoes that there is a living, breathing thing nearby; they can track CO2 from as far away as 164 feet. Larger people exhale more carbon dioxide, which may explain why adults are more likely to be bitten than children. Pregnant women are also more likely to be bitten, which could be caused by the fact that they breathe out more carbon dioxide than non-pregnant folks (and they’re also warmer, which mosquitoes like). Additionally, lactic acid (produced during exercise), acetone (a chemical you exhale), and estradiol (a byproduct of estrogen being broken down) round out the bouquet of human odors that attract the flying pests.
Other factors that make you more attractive to mosquitoes include your clothes. It’s fairly well-known that you can stay cool wearing lighter colors, but did you know doing so could also prevent mosquito bites? According to Day, mosquitoes are attracted to dark colors like reds, blues, and black.
If you’re one of the “high-attractors” who suffers from being a mosquito’s favorite target, you have the perfect excuse to stay inside this Labor Day. While you can’t really change your genetics to make you less desirable to mosquitoes, you can at least have the satisfaction of knowing you were right all along — mosquitoes really do bite certain people more often. You should also take heart in knowing that mosquito season will eventually end when the temperatures dip. Bet you’ve never been this happy for winter to start.