Sleep experts have revealed the ideal temperature for a bedroom to ensure a comfortable night of deep sleep. Thermoregulation is defined as the body's ability to maintain its core temperature regardless of external temperatures. About two hours before sleeping, the body begins to cool down, according to Gloucestershire Live reports. A spokesperson from a company specializing in air quality devices stated, "If you keep your bedroom cool, you help your body in the process of restful sleep. Conversely, if your bedroom is too hot, your body becomes fatigued, meaning you'll feel mentally and physically exhausted, and you'll face actual difficulties in sleeping." Sleep experts believe that the best temperature for a bedroom for most adults ranges between 15 to 19 degrees Celsius, and it should be dark and quiet. For children, a warmer room is generally considered better. Additionally, older adults often experience decreased levels of melatonin and cortisol and a general drop in body temperature, which may require raising the temperature in the bedroom.