How do you shower? You may be causing harm to your brain and heart – pharmacist

Between January and March 2015, 3018 participants between 18 and 65 years without a severe comorbidity (underlying health condition) and no routine experience of cold showering were randomised to a (hot-to-) cold shower for 30, 60, 90 seconds or a control group during 30 consecutive days followed by 60 days of showering cold at their own discretion for the intervention groups.

To evaluate the effect of cold showering, illness days and related sickness absence from work were recorded.

Quality of life, work productivity, anxiety, thermal sensation and adverse reactions were also monitored.

Seventy nine percent of participants in the interventions groups completed the 30 consecutive days study.