Health Benefits of a God Night's SleepSleep, we all love it, especially when we wake up from a great night's sleep._____（26）But nowadays we are beginning to understand the importance of sleep to overall health.People working the night shift have a higher risk of cancer. Researchers believe this link is caused by differing levels of melatonin（褪黑素）in people who are exposed to light at night._____（27）Melatonin makes us sleepy and is thought to protect against cancer. Be sure that your bedroom is dark to help your body produce the melatonin it needs.When your body is short of sleep, it goes into a state of stress. The body's functions give you an alarm which causes an increase in blood pressure._____（28）Learn to relax to reduce the effects of stress.Researchers have also fund that people who sleep less than seven hours per night are more likely to be fat._____（29）So if you are interested in controlling or losing weight, don't forget to pay attention to getting a good night's sleep.Sleeping during the day will protect your health and make you more productive. A study of Greek adults showed that people who slept during the day several times a week had a lower risk of dying from heart disease._____（30） _____.