Each day our bodies are being attacked by parasites. The bites from those beasts have several downsides for us.
Our bodies react to those bites with:
- Skin Irritation;
Those are the most common reactions (not to mention severe allergic reactions). The predators have their ways of locating us. The bed bug, for instance, is a heat-guided blood-drinking torpedo. The only way for us to stop being prey is to understand how they see us. To get to know the enemy and its ways.
Some people tend to be preferred as a meal from mosquitos and other insects. Those lucky few are being bitten on a regular basis. Are you a member of that club? Have you ever wondered why parasites prefer to feast on your blood? Read the rest of the article to find some answers.
The interesting thing is that some blood types emit more heat and carbon dioxide than others. Humans that are from the “O” blood type are hunted by parasites. Maybe it has something to do with the compatibility of that blood (especially the “O-”) type with others.
A research shows that mosquitoes love targets from the “O” blood type. When you think about it, the blood type is quite rare, making it sort of a delicacy for the insects. In fact, a study was conducted in which two control groups of mosquitos were released in habitat and had to choose between an ”O” blood type target and a control group.85% of the mosquitos were happy to land on the “O” blood type target. For reference, only 45% of the second group landed on “A” blood type target. This proves that the insect vampires heavily prefer blood type “O”. People with blood type “B” fall in the middle. It turns out that they emit a secrete from their skin that contains information about their blood type. Insects can decipher that odour and locate its target. Every blood type group secretes, but not every person does. Roughly 80% of people from blood group B are secretors. Respectably, bloodsucking insects want to know “What’s for dinner?” and gladly take the offers of secretors.
Secretors - A Secretor is defined as a person who secretes their blood type antigens into body fluids and secretions like the saliva in your mouth, the mucus in your digestive tract and respiratory cavities, etc. Basically what this means is that a secretor puts their blood type into these body fluids.
The pests are lured by our natural odour, which we don’t even acknowledge. No-see-ums are mainly attracted to humans because of the carbon dioxide and heat that they emit. Same goes for the mosquitos. In fact, mosquitos have a dedicated organ that they use to absorb carbon dioxide. The organ is called “maxillary palp”.
Our natural odours make us a highly attractive target for some insects. In fact, there are even species of mosquitoes that bite exclusively on ankles and feet. Believe it or not, they don’t bite because they know it will bring you high discomfort and pain in some cases. The smell of feet is what is attracting them.
The smell of your feet can attract insects. An entomologist by the name Daniel Kline conducted an interesting experiment. He wore the same pair of socks for twelve hours each day for three days. He found out (the hard way) that the odour coming from his feet was attracting insects, mainly mosquitos. The smell is due to a bacteria called Brevibacterium – the same bacteria that is used in the making of the famous Limburger cheese.
What do you know, it turns out that mosquitos are cheese enthusiasts after all!
Lactic acid is also a pleasant aroma for blood-sucking insects. In the human body, lactic acid is generated during intense exercise. While your muscles need more energy in order to do their job, your body breaks down glucose and oxidises it. The process is bringing the lactate concentrations in the body to higher levels. This reason alone makes an exercising body a higher priority to blood-drinking pests. Exercising raise your body’s temperature and the levels of carbon dioxide, therefore turning you into a target for mosquitoes and biting midges.
Your clothes are giving your position away. Many insects, such as mosquitos and sandflies, are attracted to colours that stand out in their surroundings. Yellow, red, dark blue – you should avoid those during summer nights. However, how attractive you are to the insects also depends on your current surroundings. Think of this as your camouflage. If you are in the forest, you would probably be better off wearing green and brown clothes. If you are alone though, you will still stand out on the mosquitoes’ radar. And. as with all camouflage techniques, you will have to standstill. Yes, the motion also catches the attention of these buggers.
Alcohol consumption will bring the ethanol levels in your blood to higher levels. This will increase your body temperature, making you a more obvious target for bed bugs and other “heat-guided” insects. The interesting thing with beer is that it turns out to be loved by mosquitos! Ethanol levels and heat generated from the body, are not factors that correlate with the choice of prey for mosquitos and sandflies. On the other hand, the consumption of beer does correlate with their choice! So far, it is not 100% proven why.
There is a possibility that mosquitoes can not only sense your blood type with the secrete emitted through your skin. Allegedly, they can also sense the “state” of your blood. After you have a beer or two, there will be signs of beer barm. It is known that barm can filtrate blood, meaning that after you have a couple of beers, you trick the mosquitos into believing your blood is of better quality and pure. Once again, this possibility is not yet proven, neither researched for that matter.
High levels of uric acid in the bloodstream are making some people more inviting to bloodsuckers. Uric acid is being produced by our natural ageing process. (don’t panic, it is normal). Our bodies filtrate uric acid through the kidneys and throw it away with urine. Some people can’t process the amounts their bodies produce, therefore having a higher percentage of uric acid in their blood. This makes their skin emit odours that tend to welcome midges, mosquitoes, sandflies and other blood-sucking, flying insects from the family.
A higher concentration of uric acid in your blood could also spell trouble. This acid is building up in joints and starts inflicting major pain to affected individuals. It also causes the forming of kidney stones.
However, if you are occasionally bitten by insects, it does not mean that you have a high level of uric acid! There are around 350 different odours radiating through our skin that insects can sense, and science has yet to investigate all of them. Heck, they are not even certain about the number!
Ammonia is being emitted from our bodies mainly by sweat. On it is own, it is not attracting insects. In fact, some claim it is a natural repellent. If you have a combination of ammonia and lactic acid, the effect is the exact opposite.
A study was conducted in which three compounds were tested: ammonia, lactic acid, and carbon dioxide. As you already know, carbon dioxide and lactic acid are major factors in the choice of prey for insects. You would expect a combination of either one to have an effect and lure them to you, right? Well, no! The bigger part of tested subjects (mosquitos) was attracted to carbon dioxide and lactic acid, and to ammonia and lactic acid. However, combining ammonia and carbon dioxide had no effect on the test subjects!
In essence, if you are exercising outdoors, the combination of lactic acid and carbon dioxide will make you a target. If you sweat too much, flying critters may think about attacking you.
This is only logical – after all, if you are all wet and sticky, no flying insect would want to land on your skin as it will make it an easy target. As soon as your sweat dries out, hunting season is open again! Only now you have a combination of lactic acid and ammonia with less concentration of carbon dioxide because your breathing is back to normal.
The human body can produce acetone. The process is natural, we all have ketone bodies inside of us. The problem is when our bodies produce too much. This results in Ketoacidosis, which is common for people that are suffering from type one diabetes. Among other unwanted effects, Ketoacidosis leads to a higher concentration of acetone in the human breath. On its own, it may give the breath a fruity smell. The aroma is inviting to a variety of flying insects like mosquitoes, fruit flies and others.
This is not a major factor and the aroma of acetone still has to be in combination with other factors.
Serotonin and Noradrenaline are both chemicals that are constantly present in our systems. Levels of both chemicals are going up and down in our bodies for various reasons. Bananas seem to bring those levels higher.
Insects need those chemicals to nurture their eggs and are capable of sensing them within our bodies.
Well, this is not yet tested, but one thing is certain. If you do have high levels of Serotonin and Noradrenaline in your system, you have a bullseye on your back, at least for flying menaces.
A study from 2011 shows that the bacteria living on our skin is also a factor for attracting vampire-like pests. The target of the research was the African malaria mosquito. The test concluded that people with a higher bacteria count on their skin, but less diverse, bacteria flora are “okay” with mosquitoes. This leaves people with low density, but a higher diversity of bacteria less attractive to the mosquitos. This can be the key to specialised repellents and even personalised treatments, which can prove valuable in the fight against this disease.
Keeping in mind the majority of the factors mentioned above, you can make the assumption that body type does play an important role in attracting more insects your way. For instance, if you are struggling with excessive weight, normal everyday tasks will exhaust you more than usual. It will make you sweat, stress your muscles, and you will have trouble breathing. Now, you will emit scents of ammonia, carbon dioxide, and lactic acid. If you have a beer on top of that and a banana for dessert, you might just as well just lay down and feed your new pets. Pregnant women are also physically challenged during their day-to-day life. On top of that, hormones are constantly in motion, which makes them a yummy target as well.
It is easier for us to hide from some parasites. Leeches, for instance, rarely attack big bodies, and they prefer open wounds as a source to feed on. So, if you are not running through the woods or swimming in a lake with an open wound, you should be fine. Ticks are not picky at all – anything that generates heat is a potential target. The more heat you generate, the bigger target you become for a tick.
Things get a lot more complicated when it comes to flying parasites. They tend to have specific requirements when it comes to their meals. The leading factor for those insects is the cocktail of different chemicals flowing through your body. There are more than 350 different “odours” streaming through your skin and scientists are just now starting to look into the matter.
So, for now, the above-listed points should be enough for you to at least limit the number of bites you receive during picnics and hikes. If you have any ideas and observations on what makes a specific individual more likely to get bitten, please share your knowledge with us in the comment section below!