Every time I go on holiday, I leave with my legs looking like I’ve had a serious case of adult chicken pox. I always get eaten alive by mosquitoes. Meanwhile, my friends, who have been to all the same places and done all the same things as me, somehow manage to get off scot-free. I know I’m not alone in this fury. If you think or feel like you’re an absolute bug magnet and get bitten more than everyone you know, I feel your pain – and we might be on to something.
I’ve been chatting to entomologists and pest experts to find out if some of us simply are more attractive to mosquitoes and why. The answer was both validating and infuriating.
‘It isn’t simply imagination that one person can be repeatedly bitten while somebody sitting next to them seems to escape completely,’ explains Professor Adam Hart, entomologist and professor of science communication at the University of Gloucestershire. ‘Mosquitoes use a sophisticated combination of cues to find us... Those signals vary considerably between individuals – so some people really are more attractive to mosquitoes than others.’
Now we know that we aren’t going crazy, we can get to the bottom of what exactly is attracting them and, more importantly, how to stop it. Here’s what could be making you so susceptible to mosquito bites and the experts’ tips for avoiding them.
Traits making you more likely to get mosquito bites
Exercise
‘Exercise increases several of the cues mosquitoes use to find us,’ says Professor Hart. ‘Particularly carbon dioxide output, heat and moisture – so it can plausibly make a person easier for mosquitoes to locate.’ Not sure this is quite the takeaway Professor Hart was intending, but to me, that sounds like an excuse to stop exercising in order to avoid mozzie bites, so I’ll be using that one at the gym for the foreseeable future.
Alcohol
Turns out, mosquitoes love a Friday night G&T as much as we do. ‘There is some evidence that drinking alcohol can increase mosquito attraction,’ suggests Professor Hart, ‘although this comes from relatively small studies, so I wouldn’t suggest that having a particular drink will automatically make someone a mosquito magnet.’ The idea comes from the fact that drinking alcohol causes us to sweat more and to produce more CO2 – mosquitoes’ three favourite things.
What to read next
Similar claims have been made about particular foods either attracting or repelling mosquitoes, but Professor Hart is significantly less convinced by this. ‘There isn’t good evidence, for example, that eating garlic provides useful protection against mosquito bites.’ So put down the garlic bread and wine, and pick up a glass of water instead. Sorry!
Clothing
I learned this clothing trick a short while ago and it’s revolutionised the way I look at my summer wardrobe, especially when packing for a holiday. ‘Colour is interesting because some mosquitoes also use visual cues when locating hosts,’ says Professor Hart. ‘Experiments have demonstrated preferences for particular wavelengths and colours in some species.’
What this means is that the way you dress, could be making you an easier target for mosquitoes and their bites. ‘Darker clothing can increase the likelihood of you being bitten because colours like black, navy and red stand out more to insects,’ says Adam Juson, pest expert and founder of commercial pest control specialists Merlin Environmental. The experts recommend light-coloured clothing instead, especially in countries with high mosquito numbers, as well as ensuring you cover exposed skin and wear effective repellent.
Blood type and genetics
One of the most commonly believed truths of bug bites is that those who get bitten most simply have tastier blood. After speaking to my experts, I’ve discovered there is some truth in this but mostly a whole lot of nonsense.
‘While type O blood often attracts slightly more bites than other types, genetics matters more. A couple of different studies have shown that attractiveness to mosquitoes is partly inherited,’ says Adam. If your parents find they’re particularly susceptible to bites, the likelihood is you inherited those same traits which make you stand out to mosquitoes.
‘Genetics could certainly play a role because many of the characteristics mosquitoes respond to, including aspects of our odour, are partly influenced by our genes,’ agrees Professor Hart, ‘Studies involving twins have suggested that mosquito attractiveness has a heritable component so being an “insect magnet” may, to some extent, run in families.’
However, this is not blood related as some may think. ‘One final myth I’d bust is the idea that mosquitoes are simply attracted to “sweet blood”,’ says Professor Hart. ‘They don’t somehow know that your blood tastes better before they bite you. They’re responding to a remarkably complex combination of carbon dioxide, heat, moisture and chemicals surrounding your body. Some of us simply broadcast a more attractive mosquito signal than others.’
Sweat and scent
‘This is extremely important,’ says Professor Hart. ‘Carbon dioxide is one of the major signals mosquitoes use when locating potential hosts. Once they get closer, heat, moisture and skin odours become increasingly important. Rather than responding to one thing, mosquitoes integrate several different signals when finding us.’ So sweat, as a result of body heat, massively increases a mosquito’s abilities to track you down and bite you.
‘Our skin is also home to a large community of bacteria, and these bacteria help produce some of the volatile chemicals that make up our individual scent,’ explains Professor Hart. ‘Differences in skin chemistry and our skin microbiome may therefore help explain why two apparently similar people can be very differently attractive to mosquitoes.’ You know how everyone has their own individual smell – something we ourselves can’t notice but others can? Well, mosquitoes pick up on it.
Pregnancy
While some may believe it to be a myth, it’s true – pregnancy can increase your likelihood for bug bites. ‘Pregnant women are much more likely to be bitten – the bite frequency almost doubles – due to higher body temperature and CO2 output,’ suggests Adam. Give it nine months and you may see some relief.
Skin sensitivity
Sometimes, it may just be that your body is reacting to a mosquito bite in a more obvious way.
‘One important point is that the number of bites you notice isn’t necessarily the same as the number of times you’ve actually been bitten,’ says Professor Hart. ‘People vary considerably in their inflammatory response to insect saliva. One person may develop a large, red, itchy swelling, while another has a much less obvious reaction to a similar bite. Apparent differences in how much people are being bitten can therefore reflect both genuine differences in attractiveness to insects and differences in how strongly our bodies react afterwards,’ Professor Hart explains.
Location
And while most of the reasons lie in science and your skin microbiome, the experts explain there are also just some pretty practical reasons as to why someone might get bitten more – one being where you’re sat.
‘There can also be surprisingly small-scale effects,’ explains Professor Hart. ‘Where you’re sitting, whether you’re closer to an open window and how much exposed skin you have can all influence your chances of being bitten.’
How to protect yourself from mosquito bites
Thankfully, my experts have solutions as well as causes for our bug bites. Professor Hart believes the most reliable approaches are the ones that make the most common sense. ‘Cover exposed skin where practical, use window and door screens or mosquito nets where necessary and use properly tested insect repellents. Products containing DEET or icaridin/picaridin are among the established options when used according to their instructions,’ says Professor Hart.
He also warns against supposed mosquito-repelling plants, eating particular foods, vitamin supplements, ultrasonic devices or similar home remedies. He believes there is often little evidence that these provide meaningful protection. ‘Some plants contain chemicals with insect-repellent properties, but simply having a lavender or citronella plant growing on the windowsill shouldn’t be regarded as a substitute for a properly tested repellent,’ warns Professor Hart.
Meanwhile, Adam suggests we wear light-coloured clothing, remove standing water from near our homes and using citronella and lemon eucalyptus candles (not plants) in the garden. ‘But don’t waste your money on things like ultrasonic wristbands, vitamin B or garlic supplements, or other “natural” oils,’ warns Adam, as these are simply well-intentioned rather than effective.
‘It genuinely isn’t in your head if you seem to get bitten more than everyone else. It comes down to a mix of genetics, body heat, the CO2 you breathe out and even the bacteria on your skin,’ says Adam. ‘You can’t change your biology but proven repellents and a few simple precautions can make a real difference.’
