Mosquitoes are attracted to certain compounds found in human sweat and skin bacteria. People with higher concentrations of these compounds tend to get bitten more. This includes components like lactic acid, ammonia, and certain carboxylic acids.
Carbon Dioxide
Mosquitoes are attracted to carbon dioxide, a gas produced in every exhaled breath. Individuals who exhale more CO2, like larger people and pregnant women, can be more attractive to mosquitoes.
Body Temperature and Heat

Mosquitoes can detect body heat and are more likely to be drawn to those with higher body temperatures. Exercise, alcohol consumption, and hormonal changes can increase your body temperature, making you a more likely target.
Blood Type