Marks friend says that sleep is important, but Mark disagrees. There are so many things he wants to do at night! On average, Mark gets about three hours of sleep each day, and he likes to sleep with the lights on. What is Mark risking with this behavior?
Mark is taking a lot of risks. Sleep is used to repair your heart and blood vessels. Not getting any sleep or not sleeping enough can increase the risk of heart disease, kidney disease, high blood pressure, diabetes, and stroke.
