According to Dr Nerina Ramlakhan, a sleep expert at Silentnight, the optimal bedroom temperature for sleeping is between 16C and 21C, and your brain needs to be slightly cooler than the rest of your body.
“A good night’s sleep is important in order to process information throughout the day as well as to repair and re-balance the body physically and mentally,” Ramlakhan tells The Independent.
“Ideally, in order for us to sleep well, there needs to be a fractional temperature difference between our body and our brain – a warm body and a cool head!”
1 Put your bedding in the freezer for a couple of minutes (put it in a plastic bag first though). If you don’t have much room in your fridge or freezer, even just your pillowcase or PJs will help.
2 Fill a hot water bottle with iced water and place on the ‘cooling points’ of your body: knees, ankles, wrists, neck, groin and elbows. You can also fill a hot water bottle with cool water, freeze it and take it to bed with you.
groin [grɒɪn]：n. [解剖]腹股沟
3 Moisturise before bed with an aloe vera based aftersun cream, ideally kept in the fridge.
aloe vera [,æləu'verə]： 芦荟；芦荟汁
4 Fill an empty perfume bottle with chilled water and keep it by your bedside, spray on your face, back of your neck, and back of your knees to cool down.
5 Use cotton pyjamas and thin, pure cotton sheets for your bed - high quality cotton is the ideal bedding material to sleep between to stay cool as it’s most breathable.
6 Make sure you’re not eating too much protein as this can actually heat your body up by boosting your metabolic rate, according to sleep expert Dave Gibson.
7 Eat spicy food, but at least three hours before bed - it can make you sweat which cools the body down.
8 Exercise in the morning rather than evening to stop your body getting too hot.
9 Keep your evening shower tepid to lower your body temperature. Don’t have a freezing cold one though, as your body will react to the sudden change in temperature by preserving heat.
10 Contrary to popular belief, Gibson says we should keep windows closed during the day to keep the house cooler. Keep the curtains closed too.
11 Turn off all electrical devices in the bedroom as these emit heat. Switch off sockets too.
12 Keep your feet cool, either by keeping them outside the covers or resting on an ice pack.
13 Put a roasting pan full of ice in front of a fan to cool the air.
14 Drink water regularly during the day, but not too much at night. About ½ pint before bed will be enough to keep you hydrated and prevent you from having to get up and go to the loo.
15 Sleep in a separate bed from your partner - two bodies = twice the body heat.
16 Sleep downstairs if you can as heat rises.
17 Sleep in cool, wet socks or even a damp T-shirt.
18 Rinse your wrists and feet with cold water before getting into bed.
19 If you wake up in the night, rub a menthol stick on your forehead to help cool down, Dr Ramlakhan recommends.
menthol ['menθɒl; -θ(ə)l]：n.薄荷醇；薄荷脑
20 Place a wet flannel in the fridge for an hour or so before you go to bed, and rest this on your forehead as you drift off.