UK households are being urged to drink milk before bed - in order to keep warm overnight as temperatures plummet outside.

       On Friday night, forecasters including the Met Office have warned that temperatures will plummet, with the forecast for Nethy Bridge in the Highlands set to hit-17C overnight.

       And when it's icy old out, it's difficult to know how best to keep warm safely at home overnight.

       There are plenty of tips to keep warm when the weather is freezing, from extra blankets to hot water bottles and closing curtains.

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       But one of the most effective ways to keep warm when you go to bed is drinking milk, say experts.

       That’s because the actual chemicals in milk have been shown to induce sleep as well as warming the body.

       Sleep experts Online-Bedrooms.co.uk said: “Drinking a warm cup of milk before bed will help to heat up the body from the inside.

       “Milk also contains tryptophan which helps the body prepare for sleeping.”

       According to Sleep Foundation.Org: “Limited scientific evidence suggests that warm milk before bed may help you sleep. In a study of people staying in a hospital’s heart unit, those who drank warm milk and honey for three days noticed improvements in sleep.

       “A study of adults over age 60 found that drinking fermented milk over the course of three weeks reduced nighttime wakings.

       “If you struggle with initiating sleep, milk might be able to help. In a study of people over 65, those who drank more milk and engaged in physical activity reported falling asleep more easily than those who did not.”

       In fact, using the heating isn't necessarily the best for a good night's sleep.

       Cat Wiltshire from Online-Bedrooms.co.uk added: “Sleeping with the heating on at night generally isn’t recommended and many people are looking for ways to stay warm without cranking up the heating.

       “Simple hacks such as putting a hot water bottle in bed before you get in it can go a long way when trying to achieve comfort in bed at night.

       “Having multiple layers of clothing or bedding can help to trap and keep heat and allow you to adjust the warmth by removing or adding layers.

       “Drawing your curtains in the early evening can also prevent any cold from making its way inside.

       “Instead of sleeping in thick pyjamas, opt for layers instead. This way you’ll be able to keep warm throughout the night and easily remove layers if you become too hot. Fluffy socks and thermal pyjamas are two great hacks for staying cosy.”