Why do mosquitoes bite some people more than others?
Do you feel like a real mosquito magnet, when other people around you are almost spared? This phenomenon is real and fully documented by science.
Mosquitos don't pick their victims at random. They remotely detect various biological signals emitted by the human body: carbon dioxide (CO2), body odor, heat, and chemical skin markers.
Recent studies show that some people give off signals that are significantly more attractive than others. As a result, they are stung much more frequently than average.
How do mosquitoes detect humans?
An extremely developed sensory system
Only female mosquitoes bite because they need blood to develop their eggs.
To locate a host accurately, they use a highly efficient multi-sensory detection system.
They detect at a more or less long distance:
- CO2 emissions
- body odours
- Body heat
- visual signals
This information is combined to track a human signature all the way to the source.
Why do some people attract mosquitos more?
Differences in attractiveness between individuals are mainly related to measurable biological factors.
Carboxylic acids: major attractiveness factor
A study published in Cell (2022) shows that the most stung people produce more carboxylic acids on the skin's surface.
These compounds, derived from sebum and perspiration, create a very attractive olfactory signature for mosquitoes. Above all, this attractiveness remains stable over time: a person who attracts mosquitoes one summer will also attract the next ones.
So, lactic acid and ammonia, compounds found in sweat, act as powerful attractants. People who sweat a lot or have a specific bacterial skin composition are more attractive to mosquitoes.
The role of genetics in mosquito bites
A study on binoculars published in PLOS One (2015) showed that genetic factors would explain nearly 67% of mosquitoes' attractiveness — a level of heritability comparable to that of size or IQ. In other words, if you are more stung than others, you owe a large part of it to your genes.
The skin microbiome and skin odor
Human skin is home to billions of bacteria that transform skin secretions into fragrant compounds. Depending on their composition, these bacteria can increase attractiveness or, on the contrary, reduce it. The microbiome therefore plays a central role in the body odor perceived by mosquitoes.
How do mosquitoes locate a person?
The role of carbon dioxide (CO2)
CO2 is the main signal used to detect a human at a long distance. Mosquitoes are able to follow the variations of CO2 in exhaled air and to trace this flow back to its source. The more CO2 a person emits (physical activity, high metabolism, pregnancy), the more easily they are identified.
Body heat as a proximity signal
Once close to their target, mosquitoes use heat to refine their trajectory. Warmer areas of the body become preferred sting points.
The influence of clothing color
Visual signals are involved in the final phase of the approach. Dark colors increase visual contrast, absorb more heat, and make it easier to detect the target. This is why some outfits can increase bites.
The tiger mosquito, for example, is particularly attracted to dark colors such as black, red, blue or purple. On the other hand, light colors such as white, beige or yellow attract him much less.
What science hasn't proven about mosquitos yet
Dietary supplements and mosquitos
The idea that certain supplements change body odor and reduce bites has not been reliably demonstrated.
Mosquito diet and attractiveness
The consumption of certain foods (banana, sugar, etc.) is sometimes associated with bites, but the scientific results remain inconsistent.
Individual factors that are poorly established
Stress, alcohol, or certain personal sensations can influence the body indirectly, but are not enough to explain differences in attractiveness.
Why are you more stung than the others?
The differences in bites are mainly explained by a combination of factors:
- genetic
- skin microbiome
- CO2 production
- Chemical signature of the skin
These elements create a unique “olfactory imprint” specific to each individual.
Conclusion: a precise and non-random detection mechanism
Mosquitoes use an extremely accurate detection system based on biological and chemical signals.
Some people are naturally more detectable than others, which explains the differences observed on a daily basis.
FAQ — Mosquitos and bites
Why do some people get stung more than others?
Because they emit more attractive signals such as CO2, body odors and certain chemical compounds in the skin.
Does blood type influence mosquito bites?
Some studies suggest a slight influence (especially for people in group O), but it is secondary to chemical and biological factors.
Do pregnant women attract mosquitos more?
Yes, several studies indicate that pregnant women are more attractive to mosquitoes, due to a higher body temperature and increased CO2 release.
Why do mosquitoes bite some people and not others?
This mainly depends on genetics, skin microbiome, and body emissions.
