B1 reading: Why we need more sleep

1 Most adults need between seven and nine hours of sleep a night, but many of us get much less. We stay up late to finish work, watch one more episode of a series, or look at our phones in bed. Then we drink coffee to get through the next day. It may seem harmless, but scientists say that losing sleep regularly has a real effect on our health.

2 When we sleep, the body does important work. It repairs muscles, and the brain sorts the information it has collected during the day. This is one reason why students who sleep well after studying often remember more than students who stay up all night. Sleep also helps the body fight infections. People who sleep less than six hours a night catch colds more easily.

3 A lack of sleep also affects our mood. After a bad night, small problems can seem much bigger, and we get angry more quickly. Many people also find that they want sugary and fatty food when they are tired, which can lead to weight gain over time.

4 So what can we do? Sleep experts give some simple advice. First, try to go to bed and get up at the same time every day, even at the weekend. Second, keep your bedroom cool, dark and quiet. Third, avoid screens for an hour before bed. The light from phones and laptops tells the brain that it is still daytime, so it is harder to fall asleep.

5 Caffeine is another problem. Its effect lasts for several hours, so a cup of coffee at four in the afternoon can still keep you awake at ten at night. Experts suggest having your last coffee before lunch.

6 Finally, if you can't sleep, don't lie in bed worrying about it. Get up, go to another room and do something relaxing, like reading a book, until you feel sleepy. Then go back to bed.

7 None of this is complicated, but it does need a little discipline. The reward is worth it: more energy, a better mood and a healthier body.