1SrOlNkoeOeuyWoh37NGPUA

Everything That Happens to Your Body Over the Course of a Summer

A head-to-balls-to-toe guide to what’s happening in your booze and sun-addled bod

Summer is here, which means the usual: Seeing/avoiding a dozen different superhero movies; falling asleep in a park somewhere and waking up with a farmer’s tan; and attending at least three barbecues where you get stuck talking to someone who can’t shut up about Bitcoin. But on a more personal level, your body is going to go through a number of changes with the season — here are the biggest ones…

Hair

With enough time out in the sun, your hair is going to get a bit blonder over the summer. Stylist and trichologist Julie Beale explains, “What gives our hair its characteristic color is a pigment called melanin,” and when it’s exposed to sunlight, the melanin starts to break down, thus lightening your hair. Thankfully the results are usually fairly subtle and natural-looking, so you won’t end up looking like you just took a trip to Flavortown.

Brain

Aside from the information overload you’re going to experience from movies featuring dinosaurs, superheroes and yet another blatant Die Hard rip-off (this time starring The Rock), your brain is going to feel the summer in one other significant way: You’re going to be sleepier. Sleep psychologist Charles Schaeffer explains that the longer summer days wear you out, resulting in a stronger sleep drive. Also, when you go indoors, air conditioning can confuse the body into thinking it’s getting ready for bed (since your body naturally drops a couple of degrees while you sleep). End result: Summer makes your brain sleepy, no matter where you go.

Heart

A 2013 study by the European Society of Cardiology found that risks from heart disease generally decrease during the months of summer. In part, this is because people are generally more active during the summertime, but primarily they attribute this to dietary changes. No, that doesn’t mean that daily barbecues are the key to heart health — instead, they point to the greater availability of fresh fruits and vegetables.

Skin

Exposure to the sun dries out your skin, which can result in an excess of dead skin on your body. If you don’t exfoliate really well, this can lead to clogged pores, resulting in breakouts and heat rash, says physician Ben Wedro of MD Direct. Also, if you were hiding all those secret invisible freckles from your partner, this is the season they’re going to find out about them, as the sun’s rays will trigger your skin to make more melanin, resulting in more freckles.

Gut

For the same reason your heart health improves during the summer, so does your GI tract. Gastroenterologist Nitin Ahuja says that in contrast to the comfort foods of winter, the fruits and veggies we’re more likely to eat during summertime — as well as an increased intake of Vitamin D from the sun — will likely lead to better gut function, lessening symptoms of an irritable bowel and other GI issues.

Testicles

According to sexual health doctor Joshua Gonzalez, the reason your balls dangle from your body in the first place is that the best conditions for sperm production are when your gonads are a few degrees cooler than the rest of your body. This is also why your boys shrivel upwards in the cold, and hang a bit long when they’re sweaty — like your dad endlessly messing with the thermostat, they’re striving for that perfect optimal temperature. But even with your testicles’ ability to self-regulate, the summer heat is strong enough to make a dent in your tadpole-count, says the New York Times, meaning that you may be less fertile than usual at this time of year.

Feet

During the summer, you tend to be a little less hydrated and also be on your feet a little bit more. Because of this, your feet can swell up due to water retention and swollen blood vessels (excess body heat causes them to expand). To counteract this effect, the podiatry website Healthy Steps recommends that you stay hydrated and keep your feet elevated when you can. So at least this summer, you have a medical excuse to put your feet up and drink all day.