If your Instagram feed looks anything like mine, you’ve seen them: dawn ocean dippers at Bondi, ice baths in suburban backyards, wellness influencers gasping through cold plunges while telling you it’ll change your life.

Cold water therapy is having a moment in Australia. And like most wellness trends, the truth is more complicated than the content.

What Is Cold Water Therapy?

Deliberately exposing your body to cold water for a health benefit — ocean swimming, cold showers, ice baths, or purpose-built plunge pools. Temperatures typically range from 10 to 15 degrees Celsius for general immersion, and below 10 for ice baths.

The practice isn’t new. Scandinavian cultures have done it for centuries. What’s new is the Instagram packaging and $5,000 home plunge units marketed to people who’d never heard of Wim Hof three years ago.

Where the Science Is Genuinely Promising

Mood and mental health. This is the strongest area. A 2023 study in Biology found cold water immersion triggers significant noradrenaline release — a neurotransmitter involved in mood, attention, and focus. University of Portsmouth research shows regular cold water swimming produces “cross-adaptation,” where the body gets better at handling all types of stress over time.

The ocean swimmers I know — and in Australia, there are plenty — almost universally report a mood boost that lasts hours.

Inflammation and recovery. A meta-analysis in Sports Medicine found cold immersion at 10-15 degrees for 10-15 minutes effectively reduces muscle soreness after intense exercise. But newer research suggests regular cold immersion after strength training might blunt muscle adaptation. The inflammation you’re suppressing is part of the repair process.

Metabolic effects. Cold exposure activates brown fat, which burns calories to generate heat. But we’re talking maybe 100-200 extra calories per day. If anyone tells you ice baths are a weight loss strategy, they’re overselling it.

Where the Hype Outpaces the Evidence

Immune system boosting. Some studies show elevated white blood cell counts in cold water swimmers, but there’s no strong evidence this means fewer illnesses. A 2016 Dutch study found 29% fewer sick days among cold shower takers, but it had limitations and hasn’t been well replicated.

Anti-ageing. Almost no clinical evidence in humans. Some cellular studies show cold stress activates longevity pathways, but even the researchers wouldn’t claim cold plunges slow ageing.

Detoxification. No. Your liver and kidneys handle that. Cold water doesn’t “flush toxins.”

The Australian Context

We have incredible access to ocean swimming — from Sydney’s rock pools to the Southern Ocean in Victoria. Cold water is free and available year-round in many coastal areas.

But our summer temperatures mean different risks than Scandinavia. Jumping from 38-degree heat into 12-degree water creates more extreme cardiovascular shock than from 5-degree ambient air. That temperature differential matters.

The cold plunge boom has also created a cottage industry of guided sessions. Some are run by qualified professionals. Others by someone who watched a documentary and bought an inflatable ice bath. The quality gap is real.

The better-run studios are now using technology to track outcomes more systematically. AI consultants in Sydney have been helping wellness businesses build data-driven client tracking — monitoring how protocols affect mood scores and recovery over months rather than relying on anecdote. It’s the rigour this space needs.

Safety: The Bit Nobody Wants to Talk About

The wellness community has been too casual about the risks.

Cold water shock is the most immediate danger. Your gasp reflex can cause water inhalation. Heart rate and blood pressure spike dramatically. For people with undiagnosed cardiac conditions, this can be fatal.

Hypothermia develops faster than you’d expect. Your body loses heat 25 times faster in water than in air. An unguided backyard ice bath is a genuine risk.

Who should avoid it entirely: anyone with cardiovascular disease, uncontrolled blood pressure, Raynaud’s syndrome, or cold urticaria. Pregnant women should avoid extreme cold exposure. If you take medication affecting heart rate or blood pressure, talk to your GP first.

A Sensible Approach

If you want to try cold water therapy, here’s what I’d suggest:

Start with cold showers. Thirty seconds at the end of your normal shower. Free, low-risk, and you’ll know quickly if your body responds well.

Ocean swimming: go with a group, never alone. Dawn sessions at your local ocean pool are a great entry point.

Ice baths: under three minutes initially, always with someone present. Don’t treat it as a competition.

Listen to your body. Dizzy, confused, or numb? Get out. Shivering is normal. Losing control of your movements is not.

The Bottom Line

Cold water therapy has some genuine benefits, particularly for mood and post-exercise recovery. It also has real risks that the wellness industry has been underplaying. It’s not a miracle cure for anything, but it can be a useful tool in a broader approach to physical and mental health.

The best thing about it in Australia? The ocean is right there. You don’t need a $5,000 plunge pool. You need a towel, a mate, and a bit of common sense.

Just maybe skip the part where you film it for Instagram.

Jess Morley is a Brisbane-based wellness writer and yoga instructor. She writes about evidence-based wellbeing at SoulShine.