- There are reports suggesting that bedroom temperature may have a negative effect on sleep quality.
- The evidence score is 26, and the reliability is very limited.
- This information may be useful for people considering how to manage their own bedroom environment.
Bedroom temperature refers to the temperature conditions within a bedroom.
It is generally treated as one of the factors that make up the sleep environment and is considered a factor related to sleep quality.
There is a report suggesting that as bedroom temperature rises, sleep efficiency may decrease. One of the studies introduced here included a survey of 62 adult men and women (average age 47.7). This study was conducted as a cohort study (a study that tracks a specific group over a certain period to examine associations). Over 14 consecutive days of measurement, a dose-response trend was observed in which sleep efficiency declined as temperature rose. In other words, the higher the temperature, the greater the possible impact on sleep.
Another survey looked at how differences in the environment affect sleep. In a study of 104 people living in urban Beijing, a cross-sectional study (a study that examines a state at a single point in time to look for associations) was conducted. It reported that a slightly warmer bedroom environment combined with good ventilation and low carbon dioxide concentration may be beneficial for sleep quality. Since higher temperature can be either beneficial or harmful depending on the case, it is still not known what conditions are actually favorable.
Several different methods were used across the studies. For example, an experiment involving 29 residents used a randomized controlled trial (a highly reliable research method in which participants are divided into groups to compare effects). This was conducted over 28 days, with ventilation levels examined in three stages — low, medium, and high — changed on a weekly basis. In this study, under the low-ventilation condition, carbon dioxide concentration and relative humidity increased, but bedroom temperature itself did not change. In other words, in this experiment, differences in ventilation did not change the temperature itself.
In this way, what is being compared differs from study to study. Some studies look at the relationship between temperature changes and sleep, while others look at changes in air conditions caused by ventilation levels. Understanding these differences in research methods is important when interpreting the information.
Some differences have been reported among the 3 studies examined here. While there are reports that higher temperatures negatively affect sleep quality, there are also reports suggesting that a slightly warmer environment may be beneficial. When the direction of results differs from study to study like this, the evidence score (a number representing the quality and consistency of the research) tends to be lower.
The score for this data is 26, and the reliability is very limited. This can likely be attributed to the small number of studies (only 3) and the contradictions in the reported findings. In other words, based on the current data alone, it is not possible to conclude definitively how the temperature environment relates to sleep.
| Study | Design | Number of Participants | Duration | Main Result |
|---|---|---|---|---|
| Sleep Health (2023, PMID:37076419) | Cohort study | 62 | 14 days | A possible negative effect was reported |
| The Science of the Total Environment (2023, PMID:37142023) | Randomized controlled trial (RCT) | 29 | 28 days | A possible negative effect was reported |
| Indoor Air (2021, PMID:33620120) | Cross-sectional study | 104 | 1 day | A beneficial effect was reported |
The participants totaled 195 people: 62 adult men and women with an average age of 47.7 ± 13.2 years, 29 residents of bedrooms equipped with ventilation systems, and 104 healthy subjects living in urban Beijing.
People in a variety of settings were included as study subjects — adults, residents with specific equipment, and healthy people living in a specific urban area.
The total number of studies is 3, with one each of a randomized controlled trial (RCT), a cohort study, and a cross-sectional study reported.
The study findings are contradictory, with some suggesting a possible negative effect on sleep quality and others suggesting a possible beneficial effect.
The reliability is reported to be very limited.
Does bedroom temperature affect sleep?
Studies have reported that bedroom temperature may have a negative effect on sleep quality. This is based on 3 studies.
Who participates in studies of bedroom temperature?
Participants include adult men and women and residents of bedrooms equipped with ventilation systems. Healthy subjects living in urban areas are also included.
How reliable is the research on bedroom temperature?
The total number of studies is 3. The reliability is described as very limited.
There are reports that bedroom temperature may either negatively affect sleep quality or work beneficially. Since the number of studies is small (3) and the results are contradictory, no definitive conclusion can be drawn from the current data. Why not start by checking the condition of your own bedroom environment with a self-check assessment?