Hi, I'm Craig. My grandmother was half-mosquito, and this is mental_floss on YouTube. Today I'm gonna answer locked-up time lady's big question: 'Why do mosquitoes prefer biting some people to others? Is there something we can avoid doing or do besides using repellent, like eat bananas?'

Well, time lady, you're right that mosquitoes have preferences. 10-20% of people happen to get bit more than others. And there are a few possible reasons for this, which I'm gonna tell you about today. Let's get started.

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Experts estimate that around 85% of the reason that mosquitoes prefer you is genetic. So you're pretty much born with it. It's not your good looks. Sorry about that.

Mosquitoes will especially come after you if you have the perfect combination of genetics and scent. Bon appétit. There's also stuff on your skin that attracts them. You'll probably suffer more bites if you happen to produce more lactic acid, which comes from your sweat glands. And, in 1999, it was observed that mosquitoes who carry malaria are most attracted to sweat that has been sitting on skin for a day or two, rather than fresh sweat.

They'll also prefer you if you have more of these bacteria (Staphylococcus, Variovorax) living on your skin. People who have more of these (Pseudomonas, Leptotrichia, Delftia, Actinobacteria) will have less mosquitoes to worry about. 

Blood type might have something to do with it too. A 2004 study found that mosquitoes were twice as likely to land on people who were type O rather than type B. Boy, it would suck to be part of that study. 

Type A was even less popular than type B. Plus, around 85% of us have a chemical in our skin that reveals our blood type. Mosquitoes go after those 85% of people more than the 15% who don't secrete the chemical. 

People who produce more carbon dioxide when they exhale are also more likely to get bit. A mosquito can smell this, so it'll go after them. Larger people and pregnant women suffer most for this.

Another interesting group that happens to get bit more often is beer drinkers. This might be related to carbon dioxide production as well. People tend to breathe harder after drinking beer. Or they might be a little warmer and nicer to land on. 

In your question, you mentioned that eating bananas might help the mosquitoes go away. That's actually a myth. Vitamin B12 won't work either.

Experts pretty much recommend your standard, old-fashioned bug spray. But, some work better than others. Ideally, you should use an insect repellent with around 24% of the chemical DEET. As usual, it's all in the DEET-ails. *chuckles* I'm sorry, I'm really sorry about that.

Thanks for watching mental_floss on YouTube, made with the help of these lovely skeeters. If you have a question of your own, leave it in the comments below. See you next week.