Systematic Reviews, Evidence Maps, and Big-picture Overviews
Does Cold Water Immersion Actually Improve Health and Wellbeing?
Yes, but the effects depend on timing and what you’re measuring. This 2025 meta-analysis of 11 randomized trials (3,177 participants) found cold water immersion significantly reduces stress at 12 hours, improves sleep quality, and reduces sick days by 29%. However, it also triggers short-term inflammation and shows no immediate stress relief.
Cold water immersion has exploded in popularity. Amazon ice bath sales jumped from less than 1,000 units in November 2022 to over 90,000 units just 12 months later. But does the science support the hype? This comprehensive review examined what actually happens when healthy adults take cold showers or ice baths.