Many people have experienced it: a calm outdoor gathering, and somehow one person ends up covered in mosquito bites while everyone else seems untouched. This isn’t bad luck—mosquito attraction is driven by biology, body chemistry, and environmental factors.
Only female mosquitoes bite humans because they need blood to reproduce. Over time, they’ve evolved highly sensitive systems to locate the most suitable hosts, making some people naturally more attractive than others.
A key factor is carbon dioxide (CO₂). Every breath releases CO₂, and mosquitoes are extremely sensitive to it. Taller people, those with more body mass, or anyone physically active emit more CO₂, making them easier for mosquitoes to detect. Body heat enhances this effect.
Body odor and skin bacteria also play a major role. Each person’s unique mix of bacteria produces chemical compounds that create a scent profile. Certain combinations are especially appealing to mosquitoes, and this has nothing to do with cleanliness.
