When I was little, my family spent summers in a sleepy beach town called Mallacoota.

Every morning, my sister and I faced the same choice: pool or beach?

I preferred the calm, clear pool (no sand, no waves). My sister always chose the beach, chasing surf and adventure.

If my parents had known how oceans versus pools could shape our health, maybe those debates would've ended differently.

You might not always get to choose, but if you do, that simple decision affects your skin, gut, and mental health.

So let’s dive in (for real, this time).

Love your swim, protect your skin.

Swimming does wonders for your mood, but your skin has mixed feelings.

Saltwater has soothing minerals (magnesium, zinc, potassium) that may help eczema and psoriasis¹ . My husband loves that salty, sun-kissed feeling after an ocean swim.

But once dried, saltwater pulls moisture out, leaving skin flaky, tight, and irritated.

Your skin has a microbiome (just like your gut), and a single ocean swim can change its balance (often for the better!)² .

While most new bacteria are harmless, some, like Vibrio vulnificus ("flesh-eating bacteria"), can infect wounds and cause serious illness³ . Warm waters (Florida or the Gulf) increase the risk, especially if you have fresh cuts, tattoos, eczema, or a weakened immune system.

On the other hand, chlorinated pools kill germs but also strip your skin’s protective oils and weaken its natural barrier⁴ .

The result? Chlorine leaves skin itchy, dry, and might prematurely age your skin⁵ , and makes hair and nails brittle⁶ .

This round is nearly a tie between ocean and pool. But personally, I'm team ocean. While risks like Vibrio are serious, they're also very rare.

But which ever you choose, always rinse off right after swimming and moisturise to protect your skin. If you swim regularly in a pool, consider a chlorine-removing shower filter.

Take a deep breath (but carefully).

Ever noticed how fresh ocean air clears your stuffy nose? Coastal air is naturally humid and salty: the original saline spray.

But it’s not always as pure as it feels.

When coastal waters bloom with harmful algae (Karenia brevis), the sea sprays toxins into the air, irritating your eyes and throat⁷ .

More alarmingly, studies show these airborne toxins might even cross into your brain tissue⁸ . Keep an eye out for local red-tide warnings.

Pools might seem safer, but that bleachy smell you get indoors isn’t pure chlorine.

It’s chloramines, formed when chlorine meets bodily sweat or urine in pool water⁹ .

Breathing these chemicals can cause “chlorine cough,” irritating your lungs similar to bronchitis.

On the surface, this is an even split. But the downsides are easily fixed for either ocean swimming or pools:

• Monitor your local coast authority for warnings of algae blooms.

  • Even better, become a citizen scientist, learn what to look for and contribute to bloomWatch¹⁰ .

• Check indoor pools for good ventilation, and swim outdoors if possible to avoid chlorine cough.

Germs, hormones, and your immune system.

Swimming in natural waters might help ‘rewild’ your skin and gut by introducing friendly environmental microbes we’ve lost to modern hygiene¹¹ . Think of it like playing in the dirt as a kid.

But polluted water near cities and river mouths can also carry nasty pathogens from sewage, farms, or even animal poop, especially after heavy rain.

Wait at least 24 hours after heavy rain before diving in, and steer clear of storm drains or sewage pipes¹² .

Pools, on the other hand, use chlorine to kill germs.

While chlorine does break down over time via sunlight, use, or reaction, it leaves behind chemical byproducts (DBPs¹³ ) that your body can absorb through skin or inhale.

Some studies suggest these byproducts might disrupt hormones or affect cells¹⁴ , although occasional swimmers probably don’t need to panic.

Personally, I’m a big fan of exposing your microbiome to friendly microbes. So this one seems solidly camp ocean. Just be smart about when and where you swim, especially if you live near a big city or agriculture.

Don’t drink the water (your gut hates it).

We’ve all accidentally swallowed water mid-swim, but your gut microbiome isn’t happy about it.

Ocean water’s salty, which can quickly cause stomach upset and dehydration.

Worse, oceans near cities often carry nasty germs from sewage and farms:

• Norovirus & Rotavirus (the stomach-flu gang)

• E. coli & Salmonella (the food-poisoning duo)

• Giardia & Crypto (parasites nobody wants)

One study found surfers (who inevitably swallow seawater) had 3-4x more antibiotic-resistant E. coli in their gut than non-surfers¹⁵ . They weren't necessarily sick, but had become carriers.

But swallowing chlorinated-water isn’t great either.

Animal studies show swallowing chlorine can kill your gut’s friendly bacteria¹⁶ , though these studies used relatively high concentrations.

And chlorine doesn’t catch everything: the parasite Crypto can happily survive in chlorinated pools for 10 days. Between 2009–2017, Crypto caused one-third of pool-related diarrhea outbreaks in the US¹⁷ .

This round is easy. Just don’t swallow the water in either oceans or pools!

Team pool or beach?

Regardless of what you choose, nothing beats starting your day with a swim.

It feels good, and science backs it up. One study found swimmers felt 2.3x less anxious after an easy swim¹⁸ .

Why?

Water calms your nervous system. It’s buoyancy, gentle pressure, and temperature regulation all wrapped into one¹⁹ .

Swimming also boosts your brain.

The rhythmic movements, steady breathing, and focused pacing sharpen attention and executive function (especially helpful if you’re neurospicy 🌶️❤️²⁰ ).

Your choice, ocean or pool, shapes your health in ways my family never knew on those sleepy Mallacoota mornings.

But now you do.

Keep your swims healthy with these quick tips:

🚿 Rinse after: Protect your skin and hair from chlorine, salt, and germs.

🧴 Moisturize: Lotion after swims locks in moisture. Ceramides and niacinamide win extra points.

👃🏻 Drain your ears, cover your nose: Keep germs out with ear plugs and nose clips if you're prone to infections.

🦠 Monitor water quality: Wait 24 hours after heavy rain. Skip cloudy, smelly spots (likely algae), and swim away from pipes.

🫗 Don't swallow the water: Ocean or pool, your gut will thank you.

🩹 Cover wounds, skip swimming if sick: Waterproof bandages protect cuts. Wait 2–4 weeks for tattoos to heal. And if you're sick, stay out (chlorine takes time to work).

🧂 Salt beats chlorine: Choosing your own pool? Opt for gentle saltwater chlorination.

Now get off your laptop, and go enjoy a summer swim!

Reviewed by Julija Rabcuka, BA (Oxon), MSc, PhD (ABD), University of Oxford.

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