It has to do with how you smell.
If you are as unlucky as me, then you may be one of those people who seems to be a bullseye for all the mosquitos — accumlating lots and lots of bites all over your arms and legs. And your friends sitting right next to you don’t have a single bite. Why is this?
As it turns out, how attractive you are to mosquitos may have less to do with how your blood tastes and more to do with how you smell.
There are trillions of microbes that live on our skin and they all play a major role in our body odor. In fact, without these bacteria, human sweat would not smell like anything — which would actually be a blessing in certain situations. All of our bodies are different, and the types of bacteria on each of us varies quite a bit because they are, in part, influenced by our lifestyle.
A study conducted in 2011 found that the microbes found on our skin produce different chemicals, and some of them smell more attractive to insects — particularly mosquitoes.
The study involved 48 male volunteers refraining from alcohol, garlic, spicy food and showers for two days, since these interfere with the kinds of microbes that thrive on human skin. The men also wore nylon socks for 24 hours to build up a collection of skin microbes, which the researchers then used to collect their scent and use as bait for some malaria-carrying Anopheles gambiae mosquitoes.
Out of the 48 men, nine were found to be extremely attractive to mosquitoes, while another seven men were mostly ignored. To figure out why, the researchers looked at the microbe profiles of each of the men.
It turns out, the “highly attractive” group had more than twice the concentration of one common skin microbe, and more than three times the concentration of another common microbe compared to the “poorly attractive group.” The poorly attractive group was found to have a more diverse bacterial colony on their skin — meaning some people’s smell may act as a natural mosquito repellent.
The researchers also looked at how smells influence the behaviour of the mosquito species, Aedes aegypti, responsible for transmitting the Zika Virus and Dengue Fever. What they found is that skin microbes that produced lactic acid combined with carbon dioxide when we exhale, makes a combination that attracts female mosquitos.
So, you may be wondering if there is anything we can do to make ourselves smell less attractive to these pesky insects?
Unfortunately, no. The types microbes on our skin arise from genetics — which we can’t change. There really is nothing you can eat or drinking that will stop you from being bitten by a mosquito.
However, as it was mentioned earlier, these microbes are on our skin partially because of our lifestyle and the production of lactic acid by microbes when we sweat. So, definitely do not exercise near a marshland — you are just asking to get bitten!
Understanding the diverse microbe colonies on people found less attractive to insects could lead to the development of better insect repellents in the future. But for now, the best thing you can do to protect yourself from bites is to wear mosquito repellent! It only takes one bite to contract a virus.