After much back and forth about why mosquitoes bite some people more than others science has reached a conclusion. The amount of carboxylic acid your skin produces seems to determine how alluring you are to these insects. People who generate higher levels of this compound tend to emit a distinctive body scent that acts like a mosquito magnet while those with lower levels are less noticeable to mosquitoes.
That is the central finding of a study published by researchers from Rockefeller University in New York. The work appeared in Cell and it challenges many popular theories about what attracts mosquitoes, which often lacked scientific backing.
Researchers showed that the acids released from human skin can create an irresistible aroma for mosquitoes. These substances form a group of molecules secreted by each person in varying amounts and compositions and effectively mark personal identity through scent.
There is a strong link between high levels of these fatty acids on the skin and being a magnet for mosquitoes, according to Professor Vosshall.
64 volunteers wore socks on their arms
This discovery came after three years of testing. Sixty four volunteers wore nylon stockings on their arms so that the molecules of their skin could be transferred to the fabric. The researchers conducted twenty three hundred tests, showing mosquitoes a range of sock pairs to determine which scent they preferred.
In the experiments the mosquito species Aedes aegypti, a major vector for diseases such as Zika dengue yellow fever and chikungunya, was observed as it followed various tubes toward a sock to see how the insects navigated the scent trails.
During the trials the participant labeled as Subject 33 attracted far more mosquitoes than the rest, while Subject 19 drew the least attention. The trials were blind so scientists did not know who wore which stocking, yet the tests consistently highlighted a surprising pattern. When the trial began the insects swarmed toward Subject 33, a moment observed quickly by the team.
Right after the trials the team analyzed the volunteers to identify what set some apart. Chemical analysis revealed about fifty molecular compounds present on the skin of participants. Those who drew more mosquitoes produced noticeably higher levels of carboxylic acids than others. This class of acids is partly produced by skin bacteria and helps shape the human body odor that each person carries and recognizes as a signature scent.
This insight points toward practical paths for reducing mosquito bites, including products that limit these acids or alter the bacteria responsible for producing the distinctive odor. The experiments extended to additional participants and yielded similar results with the same mosquito species.
The work is reported as a reference on the topic and remains consistent with broader science on body odor and vector attraction. The study is cited as Cell 2022 for further reading [Cited: Cell journal 2022].