We’re all probably familiar with the itchy red bumps that develop after we’re bitten by mosquitoes. Most of the time, they’re a minor annoyance that goes away over time.

But do you ever feel like mosquitoes bite you more than other people? There may be a scientific reason for that!

Keep reading to find out what attracts mosquitoes to bite, why the bites itch, and much more.

A variety of factors can attract mosquitoes to you. Here are a few:

Carbon dioxide

We all emit carbon dioxide when we breathe out. We also produce more when we’re active, such as during exercise.

Mosquitoes can detect changes in carbon dioxide in their environment. Research has shown that different mosquito species may respond differently to carbon dioxide.

An increase in carbon dioxide can alert a mosquito that a potential host is nearby. The mosquito will then move toward that area.

Body odor

Mosquitoes are attracted to certain compounds that are present on human skin and in sweat. These compounds give us a specific odor that can draw mosquitoes in.

Several different compounds have been identified as being attractive to mosquitoes. Some that you may be familiar with include lactic acid and ammonia.

Researchers are still investigating the causes of the variations in body odor that make certain people more attractive to mosquitoes. Causes could include genetics, certain bacteria on the skin, or a combination of both.

Body odor itself is determined by genetics. If you’re related to someone who is often bitten by mosquitoes, you may be more susceptible too. A study published in 2015 found that mosquitoes were highly attracted to odors from the hands of identical twins.

Skin bacteria also play a role in body odor. A 2011 study found that people with a high diversity of microbes on their skin were less attractive to mosquitoes.

The researchers also identified specific species of bacteria that were present on people who were highly and poorly attractive to mosquitoes.

Colors

Research has shown that mosquitoes are attracted to the color black, but little is known about why. Regardless, if you’re wearing black or other dark colors, you may be more attractive to mosquitoes.

Heat and water vapor

Our bodies generate heat, and the levels of water vapor close to our skin can vary depending on the surrounding temperature.

As a mosquito gets closer to us, it can detect heat and water vapor. This can play a role in whether it decides to bite. One study found that mosquitoes move toward nearby heat sources that are at a desired temperature.

These factors can also be important for host selection. Other animals may have differences in body temperature or water vapor throughout their bodies. These variations could be unattractive to mosquitoes that prefer to feed on humans.

Learning

Mosquitoes could learn to prefer a certain type of host! They may associate certain sensory cues, such as scents, with hosts that have given them a good-quality blood meal.

An older study of transmission of mosquito-borne disease found that 20 percent of hosts accounted for 80 percent of disease transmission in a population. This could mean mosquitoes are choosing to bite only a fraction of people within a population.

Alcohol

A small 2002 study looked at the effects of alcohol consumption on attractiveness to mosquitoes. The researchers found that people who had consumed beer were more attractive to mosquitoes than people who had not.

Pregnancy

Studies have shown that mosquitoes appear to be more attracted to pregnant women than non-pregnant women. This may be because pregnant women have a high body temperature and exhale more carbon dioxide.

Generally, mosquitoes will bite any skin they have access to in order to get a blood meal. However, they may prefer certain locations.

One older study found that two species of mosquito preferred to bite around the head and feet. Researchers believed that the skin temperature and number of sweat glands in these areas played a role in this preference.

When a mosquito bites you, it inserts the tip of its mouthparts into your skin and injects a small amount of its saliva into your bloodstream. This helps keep your blood flowing as the mosquito feeds.

Your immune system reacts to the chemicals in the mosquito’s saliva, causing a reaction that can include redness, swelling, and itching.

More serious reactions

Some specific groups of people may experience a more serious reaction to mosquito bites, with symptoms such as low-grade fever, larger areas of redness or swelling, and hives.

These groups include:

  • children
  • people with a weakened immune system
  • adults not previously exposed to the bite of a specific mosquito species

Although it’s rare, a serious reaction called anaphylaxis can happen in response to mosquito bites. This is always a medical emergency and can include symptoms like hives, difficulty breathing, and swelling of the throat.

If you’ve been bitten by a mosquito, there are things you can do to help relieve the swelling and itch. Here are some suggestions:

  • Avoid scratching. Scratching can increase swelling, and it breaks your skin, putting you at risk of an infection.
  • Apply cold to the site. Using a cool compress like a wet towel or cold pack can help with swelling and itch.
  • Use lotions or creams. There are a variety of itch-relieving creams available for purchase, including hydrocortisone cream and calamine lotion.
  • Consider over-the-counter (OTC) antihistamines. If you have a stronger reaction to mosquito bites, you may want to take an OTC medicine such as Benadryl.

Most mosquito bites should go away in a few days. See your doctor if a bite looks infected or if you have other symptoms associated with the bite, such as fever, aches and pains, or headache.

If you’re going to be in an area where mosquitoes are present, take steps to prevent being bitten. While mosquito bites are mostly just annoying, they can sometimes spread disease.

Some tips to help prevent mosquito bites include:

  • Use an insect repellent. Examples of active ingredients to look for include DEET, picaridin, and oil of lemon eucalyptus.
  • Wear long sleeves and pants, if possible. This can limit the area available for mosquitoes to bite.
  • Choose light-colored clothing. Mosquitoes are attracted to black and darker colors.
  • Avoid peak mosquito times. Mosquitoes are most active at dawn and dusk. If possible, avoid going outside at these times.
  • Eliminate mosquito habitats. Get rid of any standing water in things such as gutters or buckets. Change water in wading pools or birdbaths frequently.
  • Keep mosquitoes out of your house. Don’t leave doors and windows open without screens in place. Make sure window and door screens are in good shape.

Why do mosquitos bite?

Only female mosquitoes bite. This is because they require blood to produce eggs.

Once the female mosquito has had a blood meal, she can produce and deposit her eggs. A female mosquito can produce 30 to 300 eggs at one time! To lay another set of eggs, she’ll require another blood meal.

Male mosquitoes don’t feed on blood. Instead, they eat nectar and juices produced by plants.

If you feel like mosquitoes bite you more often than other people, you may be onto something! Several specific factors can attract mosquitoes, including the carbon dioxide you exhale, your body odor, and your body temperature.

A combination of these factors likely makes certain people more attractive to mosquitoes. Research on this topic is ongoing.

Since mosquitoes can transmit disease, take steps to protect yourself if you’re going to an area where they may be present. If you’re bitten, the resulting bump should go away in a few days and can be treated with creams, lotions, and cold therapy.