Sleep and immunity are closely linked. Poor quality sleep is linked to a higher susceptibility of getting sick. In a study conducted on 164 individuals, people who slept for less than 6 hours were more likely to catch a cold than those who slept for 6 hours or more each day.
That is why when we are sick, we are advised to sleep more in order to allow our immune system to fight the illness easily.
While adults should aim for at least 7 hours of sleep every day, teens should sleep for 8-10 hours every day.