Making sure your bedroom is between 20-25C (68-77F) at night is key to a good sleep, according to a new study.
Researchers have discovered that sleep can be most efficient and restful for older adults during a specific temperature range.
Quality of sleep drops at higher and lower levels – highlighting the importance of ensuring the bedroom is not too hot or cold, they said.
The team, from the Hinda and Arthur Marcus Institute for Aging Research in the US, asked 50 people aged 65 and over to wear sleep monitors for a year and a half.
The study was conducted in Boston, a coastal city with warm and humid summers and cold and stormy winters, and participants slept in their own homes.
Scientists collected data on 11,000 nights of sleep in total, as well as information on participants’ sleep environments.
Analysis revealed participants had the most efficient sleep when the bedroom temperature was between 20 and 25C.
They were also the least restless during this temperature range, while 20C appeared to be linked to the longest time asleep.
The team found a 5-10 per cent drop in sleep efficiency as the nighttime temperature increased to 30C, with participants being the most restless at this level.
Previous studies suggest this drop is large enough to influence cognitive performance, stress, activity, anxiety, mood and fatigue.
And the effect on sleep was similar in size to that of drinking alcohol in the evening or experiencing chronic pain.
Writing in the journal Science of the Total Environment, the researchers said: ‘Overall, our findings indicate an optimal range of temperature, whereby sleep was most efficient and restful when nighttime ambient temperature was between 20 and 25C.
‘Our observations point to an exciting opportunity to potentially improve sleep within the older adult population by creating a more comfortable home environment.’
Lead author Amir Baniassadi warned the findings ‘underscore the potential impact of climate change on sleep quality in older adults’.
