Dreaming is still a forceful job that requires a lot of effort. Not long ago, an American scientist measured the temperature of more than 50 different animals during sleep and found that whether it was a polar fox in the freezing cold or a small animal in the African heat, the temperature around the skin was 27 degrees Celsius. This significant finding indicates that sleep is an energetic phenomenon. After falling asleep, the body radiates energy through the expansion of blood vessels, which can drop by 0.8°C in 90 minutes. The lower the temperature of the brain, the less energy it consumes. In this way, the brain can store appropriate energy during the initial stage of sleep for later consumption during dreaming. Because the process of dreaming, the brain’s intense movement requires a lot of oxygen and glucose consumption. This finding suggests to us that the dinner meal is still about quality, the purpose is to prepare enough energy for your good dreams.