Sleeping in wool PJs creates a “thermal comfort zone” conducive to restful sleep, according to a study by the University of Sydney. Researchers found sleeping improvements for all ages, but those aged 65 to 70 had the greatest benefit, falling asleep on average in 12 minutes, compared to 27 minutes for those wearing cotton. Researcher Dr Paul Swan, from the University of Sydney, says sleeping under wool bedding was the norm not so long ago and that wool helps regulate body temperature, which then helps people fall asleep more quickly, sleep longer and also have a better quality sleep. Having the bedroom at the wrong temperature is also thought to play a role in sleep disruption. Experts recommend having a room temperature of just over 18°C.