What if a single daily habit could trim your bills, boost your health, and shrink your carbon footprint—without costing a cent? That’s the promise of cold showers, a practice gaining traction across Europe as a simple, personal climate action. But as a new study shows, there’s a catch: the initial discomfort is real, and not everyone gets past it.
Psychologist Dr Lena Glaser, who led the research, sees cold showers as a test case for a broader question: can small, rewarding changes to daily routines be more effective at driving long-term green behaviour than policies that feel like sacrifices? “When people see a personal benefit from changing their behaviour and don’t feel that they’re giving something up or missing out, they’re more motivated to stick with it,” she says.
The study: 719 participants, 12 weeks, and a lot of shivering
Glaser recruited 719 healthy adults aged 18 to 65 across Europe, none of whom already took cold showers. For three months, they were asked to turn the dial down as far as they could tolerate. The results, published in the journal Environmental Research and Public Health, were striking—but not without attrition.
“A number of participants quit within the first two weeks,” Glaser admits. “But after that, the dropout rate declined. That suggests people gradually get used to it.” Those who stayed reported feeling more awake and refreshed immediately after each shower, and many took pride in pushing through the discomfort. Over time, they noted improvements in physical and mental health—benefits that translated into measurable outcomes: on average, the cold-shower group took 31% fewer sick days than a control group.
While scientific evidence on cold water immersion remains limited, the practice has a devoted following worldwide, with enthusiasts citing better mood, increased energy, reduced inflammation, and a stronger immune system. Glaser’s study adds a layer of real-world data to those anecdotal claims.
The climate and cost benefits
Beyond health, cold showers offer a tangible environmental payoff. A typical 40-litre shower lasting three to four minutes, when cooled from 40°C to 15°C, saves about 1.3 kWh of energy—enough to run a load of laundry or charge a phone 100 times. Over the 12-week study, each participant cut their CO2 emissions by roughly 15 kilograms, equivalent to driving 100 kilometres.
That might sound modest, but scaled across millions of households, the cumulative effect is significant. And because cold showers discourage lingering, they also reduce water consumption, adding to the savings on utility bills.
Glaser is quick to note that the study didn’t control for participants’ pre-existing environmental attitudes, so the results may not apply to everyone. Still, she believes the approach has merit. “The water doesn’t have to be equally cold every day. We don’t feel equally brave every day, and that’s okay,” she says. “It’s important to listen to your body and pay attention to how you feel. But sometimes it’s worth pushing yourself a little.”
For those tempted to try, she suggests starting gradually—perhaps turning the dial down for the last 30 seconds of a warm shower—and building up tolerance over time. Even small reductions in temperature can have a positive effect, she says.
The study comes at a time when European climate policy is under scrutiny. As the EU pushes for deeper emissions cuts, health-focused climate plans are gaining attention, but the gap between ambition and action remains wide. Meanwhile, public health experts are urging the WHO to declare climate change a health emergency, underscoring the link between environmental and personal wellbeing.
Cold showers won’t solve the climate crisis alone, but they offer a rare win-win: a personal health boost that also trims emissions and costs. The catch? You have to get past the first few minutes. As Glaser puts it, “Taking a cold shower isn’t exactly pleasant, but it’s a small change to make.”
