Summer is officially here, with its usual comely disposition and clammy conundrums. Do hot drinks cool you down? Why do we love beaches so much? And what actually is that mosquito’s problem? These are just a few of the questions to which Gloucester University science kingpin, Professor Adam Hart, has the (mostly) definitive answers…
Does the sun actually make me happier?
In a word, yes. Seasonal Affective Disorder (SAD) is a type of depression that’s triggered in some people during the autumn and winter, and seems to be closely related to a lack of sunlight. “Although we’re still working out exactly why ‘no sun = SAD,’ it seems likely that a lack of sunlight lowers serotonin levels,” say Hart. “Serotonin is the ‘happy hormone,’ so if the sun is shining and you feel like dancing, now you’ll know why.”
Can a hot drink help cool me down?
As ridiculous as it sounds, there’s some science behind this idea. “Drinking a hot drink causes receptors on our tongue to send a message to our brain that it’s getting hot — our brain responds by making us sweat, which evaporates on our skin and cools us down,” says Hart. “All well and good, right? But there are some problems with this counter-intuitive set up, not least of which is the fact that sweating profusely isn’t always a desired outcome. Also, if you’re somewhere humid, sweat can’t evaporate, so you’ll just end up hotter and wetter. In short, an ice cream is always going to feel more refreshing on a hot day than a steaming mug of coffee.”
Are cold showers better for me than hot ones?
“The problem here comes down to what we mean by ‘better,’” insists Hart. “Fans of cool showers (as opposed to cold showers, which are just plain wrong) are quick to point out the benefits, including keeping our skin and hair in better condition and stimulating fat burning. Cool showers also increase alertness, but to be fair, so does being chased down by a pack of dogs, and I wouldn’t choose to start my day that way, either.”
The main thing is getting the temperature right. Tepid showers are the way forward when it comes to sweating less, and the logic is simple: You sweat when your internal thermostat perceives the outside temperature as notably warmer than your body. If you spend five minutes freezing yourself, your body will register, say, the gym locker room as being overly warm in comparison, and start sweating to cool you down. If your shower is at room temperature, you’ll sweat less when you step out. Sorted.
Why do we humans love beaches so much, anyway?
“Perhaps back when modern humans were evolving we were drawn to shorelines because they’re so rich in food — those ancestors with nervous systems that were attracted to the sights, sounds and smells of the sea may have prospered,” ponders Hart. “Or it could just be that the combination of space, blue sea, gentle wave sounds and that salty smell are something that our brains associate with being relaxed. Many of us have happy memories of the seaside as children, which might also be a factor in why we return to the beach. Sadly, the reality of being crammed in cheek-by-jowl with every man and his incontinent dog on a stinking stretch of sand, most of which has invaded every millimeter of your body, rarely matches up to the romantic ideal.”
It’s hot, I’ve nailed a Slurpee and now I have “brain freeze.” Whyyy?
“Ah, the curse of sphenopalatine ganglioneuralgia, which is the proper term for this most summery of sensations,” nods Hart. “Brain freeze — that awful pain you get when you have a slush drink or eat an ice cream too quickly — is a severe but short-lived headache. It comes on because you suddenly cool the back of your throat, affecting the carotid artery that runs to the brain. The brain does all it can to protect itself from this sudden (and as it sees it, potentially threatening) onslaught, and the pain of brain freeze prevents you piling on more of the same treatment…at least for a couple of minutes.”
What actually happens to my body when I get sunburnt?
In short, things that aren’t in any way good. “Sunburn is a form of radiation burn — that’s always worth bearing in mind the next time you pass on the sunscreen,” says Hart. “Being out in the sun exposes us to UV radiation, and too much of that damages our skin, causing the red burn sadly familiar to most of us. Oh, and it leads to skin cancer. You aren’t tougher than the sun, so put on a hat and apply sunscreen.”
Why do mosquito bites itch? And what’s the best way to relieve them?
“Female mosquitoes bite us to get the blood meal they need to make eggs,” explains Hart. “To do this, they pierce our skin with their sharp tube-like mouthparts and inject a little saliva — this contains an anticoagulant, which stops our blood from clogging their ‘straw.’ It’s the anticoagulant that’s the cause of the itch, but not directly: Our immune system detects it as ‘foreign’ and mounts an attack against it, triggering a histamine response that can often go overboard and result in inflammation and that familiar itch. Some people are very sensitive, just like some people get hay fever, while others barely react at all.”
So, what’s the best way to relieve the itch you ask? “Don’t get bitten in the first place! Cover up your skin and use a bug repellent. If you are bitten, use an antihistamine cream and try not to scratch.”
Wasps are idiots. What’s with the whole premeditated buzzing-round-your-barbecue-guests thing and being all intimidating and that?
“Wasps, like their relatives the bees and the ants, are very good navigators,” says Hart gleefully. “This makes good sense because they have to head out to find food, then find their way back to the nest. One way they do this is to use landmarks in the environment, which they fly around to get their bearings. Good landmarks include things that stand out from the background, like fence posts, trees, and well, you. Of course, when a landmark starts moving, the wasps get a bit confused and start to circle more intently. When that landmark starts swatting them, then they defend themselves the only way they know how.”
What actually happens if I look directly in the sun for too long?
“It’s a bit like asking what happens if you leave your hand in the fire too long — most of us aren’t stupid enough to do it,” laughs Hart. “Just to cover some basics here, the sun is really bright. Staring at it like a drooling idiot could cause solar retinopathy, where the UV radiation that causes sunburn does similar damage to our retina, the light sensitive layer at the back our eye. In serious cases it can cause permanent eye damage and loss of sight. So, file under important things to avoid, like angering a hippo, or opening beer bottles with your teeth.”