Human: I've heard that a good night's sleep is essential for good health. Is there any scientific evidence to back this up? Assistant: 
Yes, there is scientific evidence to support the importance of getting enough sleep for optimal health. Studies have shown that people who get less than 6 hours of sleep per night are more likely to experience fatigue and other health problems. In addition, studies show that sleeping fewer than 7 hours per night can increase your risk of heart disease, diabetes, obesity, depression, and certain types of cancer.