Why Some People Are More Attractive to Mosquitoes, According to Research

Mosquitoes are drawn to certain individuals due to factors like carbon dioxide emissions, body heat, and sweat composition, according to research by Dr. Joel Riffell, a neurobiologist at the University of Washington. These cues, which vary among people, influence why some are more “attractive” to mosquitoes than others.

Carbon Dioxide and Body Heat: Primary Attraction Signals

Mosquitoes detect carbon dioxide (CO₂) from up to 50 meters away, using it to locate potential hosts. Higher CO₂ levels, often linked to physical activity or metabolic rate, make individuals more visible to mosquitoes, Riffell explains. Once closer, they are guided by body heat, with warmer bodies acting as a secondary attractant.

“When you’re active, your heart rate increases, leading to more CO₂ exhalation, greater heat emission, and increased sweating—each of which amplifies your attractiveness to mosquitoes,” Riffell says.

Sweat Composition: The Role of Chemicals

Sweat contains compounds like lactic acid, ammonia, and uric acid, which mosquitoes find appealing. A 2019 study in the *Journal of Insect Science* found that lactic and carboxylic acids in sweat are critical for mosquito attraction. A 2023 paper in *Nature Communications* further confirmed that mosquitoes exhibit preferences for specific carboxylic acids and CO₂, though individual variations exist.

“People with higher levels of carboxylic acids in their body odor are often termed ‘super attractors,’ but the exact compounds involved remain under investigation,” Riffell notes.

Skin Microbiome: A Unique Scent Profile

The skin’s microbiome—comprising bacteria, fungi, and oils—interacts with sweat to create a distinct odor. This microbial profile can influence mosquito behavior, though the mechanisms are not fully understood. A 2023 review in *Frontiers in Microbiology* highlighted that certain bacterial species, such as *Staphylococcus* and *Corynebacterium*, may enhance attractiveness by producing volatile compounds mosquitoes detect.

“The relationship between the microbiome and mosquito attraction is complex and still being unraveled,” Riffell says.

Alcohol Consumption: A Double-Edged Sword

Drinking alcohol, particularly beer, may increase mosquito attraction. A 2025 study in *PLOS ONE* (unpublished at the time of writing) suggested that mosquitoes are drawn to the unique chemical signature of beer, including ethanol and hop-derived compounds. Riffell explains that alcohol raises body temperature and increases perspiration, both of which can make individuals more appealing to mosquitoes.

“The exact link between alcohol and mosquito behavior requires further study, but the physiological changes from drinking are well-documented,” Riffell says.

Blood Type and Mosquito Preference: Mixed Evidence

Early studies, including a 2004 paper in *Medical and Veterinary Entomology*, suggested mosquitoes prefer individuals with type O blood. However, subsequent research has cast doubt on this claim. A 2017 retraction of one such study highlighted methodological flaws, and current consensus emphasizes that blood type is not a reliable predictor of mosquito attraction.

“The evidence for blood type influencing mosquito behavior is inconclusive,” Riffell states. “More rigorous studies are needed to clarify this relationship.”

Practical Tips for Reducing Mosquito Attraction

While mosquitoes are naturally drawn to certain cues, individuals can minimize their risk by:

• Reducing physical activity during peak mosquito hours (dusk and dawn).
• Using repellents containing DEET or picaridin.
• Wearing long, light-colored clothing to avoid heat retention.
• Limiting alcohol consumption before outdoor activities.

“Understanding these factors helps individuals take proactive steps to protect themselves, though no method is 100% effective,” Riffell says.