By Basant El-Faramawy
A new 12-week trial involving 719 Swiss adults found that taking regular cold showers lasting 30 to 120 seconds at temperatures as low as 59 degrees Fahrenheit (15 degrees Celsius) led to participants reporting feeling more awake and taking 31 percent fewer sick days, researchers from the University of Basel announced Thursday.
Study Details
Participants aged 18 to 65 who maintained the practice said they felt more driven and enthusiastic throughout the day after pushing themselves outside their comfort zone, according to university psychologist Dr. Lena Glaser. Of the initial 735 enrollees, 16 dropped out in the early weeks, though the dropout rate declined over time, suggesting people gradually adapt to the routine.
Supporting Research
The findings align with previous studies, including a 2025 Harvard study linking cold showers to higher quality of life and reduced stress levels for up to 12 hours after ice baths, and a 2016 Dutch study showing a 29 percent reduction in sick days among those who switched to cold showers for 90 days.
Physiological Effects
Experts say cold-water immersion may boost mental and physical health by increasing endorphins, reducing harmful inflammation, and improving circulation. The sudden temperature drop causes blood vessels to constrict, flushing out inflammation when the body reheats, while the strain of cold stimulates blood flow to maintain core temperature.
Guidelines and Risks
For those considering cold showers, UCLA Health orthopedic surgeon Dr. Sharon Hame recommends starting with water below 60 degrees Fahrenheit (15.5 degrees Celsius) for 30 seconds and gradually increasing duration over weeks. However, people with cold-induced hives, heart disease, or Raynaud’s syndrome should consult a physician first, as sudden cold exposure can spike blood pressure and heart rate, potentially causing irregular heartbeat, the Cleveland Clinic warns.
