The Scientific Reason You Are (Or Aren’t) a Mosquito Magnet

One of the 12 most dangerous bugs you need to watch out for in summer is mosquitoes. But no matter how hard you try, some people naturally attract mosquitoes more than others. Here’s why.

Your breath attracts mosquitoes

One of the most important facts to remember is that mosquitoes track people down by smell and body odor. Female mosquitoes rely on all sorts of sensory information cues when deciding which people to bite. The carbon dioxide people exhale, along with chemicals from the skin, create an “odor plume” that mosquitoes can detect from up to almost 100 feet away, says Bart Knols, PhD, a vector biologist who studies mosquitoes. “Each person gives off more than 300 chemicals from the skin, more than 100 in exhaled breath,” Knols says.

Interestingly, mosquitoes are attracted to humans by the carbon dioxide we exhale, but as they get close, they typically veer away and head to exposed areas of skin instead, according to study in Cell. Researchers found that the same receptors that mosquitoes have that detect the odors in breath also pick up the smells in skin. That explains why mosquitoes are attracted to smelly items like stinky socks, worn clothes, and bedding—even when there’s no carbon dioxide around. Check out these 10 ways to prevent mosquito bites when you sleep.

Your smell attracts mosquitoes

The specific compounds on the skin that mosquitoes respond to vary by species. The yellow fever mosquito and Asian tiger mosquito, for example, respond well to lactic acid from skin. African malaria mosquitoes respond to a blend of fatty acids, according to Knols. Your individual mix of compounds and smells determine how much of a mosquito magnet you are, depending on the mosquito species.

The blend of chemicals you produce is only partially in your control. These chemicals depend on your genetic makeup, health status, diet, skin pH, and microflora, Knols says. Microflora are the microorganisms that live on the skin.

“Bacteria on the skin break down the compounds that we give off through our pores, and these are the attractive smells,” Knols says. “So it is not actually us that attract mosquitoes, but the bacteria on our skin.”

Although this is a complex and partially understood phenomenon, Knols says that everyone has a unique smell based on individual bacteria flora species and the density of bacteria.

There are many myths and folklore stories about why some people are more or less attractive to mosquitoes. Some people falsely think having “sweet blood” or your blood type are factors. Others believe taking vitamin B or eating garlic makes people less attractive to mosquitoes. But Knols notes there’s no scientific data backing these claims. Check out these weird reasons you could be getting bitten.

Here’s how to keep mosquitoes away

If you are a mosquito magnet, you’ll want to invest in a proper repellent—like this one—to apply to all exposed body parts. “DEET, picaridin, or lemon-eucalyptus oil (with elevated concentration of citriodiol) are good repellents,” Knols says. Citronella, another popular option, only protects for a short amount of time. That’s not the case for these 9 things mosquitoes absolutely hate.