Warm Shower or Bath Before Bedtime Improves Sleep: Meta-Analysis Evidence
How Much Does a Warm Bath or Shower Before Bed Improve Your Sleep?
Passive body heating through warm baths or showers taken 1-2 hours before bedtime significantly improves sleep quality and reduces sleep onset time, according to this comprehensive meta-analysis of sleep studies. The research found that warm water immersion (40-42.5°C or 104-108.5°F) for 10-15 minutes reduces sleep onset latency by an average of 36% and improves subjective sleep quality ratings. The optimal timing is 90 minutes before desired bedtime, allowing the body’s natural cooling response to align with circadian sleep signals. This simple intervention works by manipulating the body’s thermoregulatory system to facilitate the core temperature drop necessary for sleep initiation.