How much sleep is enough for adults and for adolescents?
Julio Fernandez-Mendoza: Adults who report getting about seven to eight hours of sleep per night generally have the best health, in terms of both physical and mental health, and longevity.
But that recommendation changes with age. Adults over age 65 may need just six to seven hours of sleep per night. So older people, if otherwise healthy, should not feel anxious if they're getting just six hours. Young people need the most – at least nine hours – and some younger children may need more.
How can insufficient sleep harm our health?
Fernandez-Mendoza: Our team was the first to show that those complaining about insomnia – difficulty falling or staying asleep – were more likely to have high blood pressure and be at risk for heart disease.
In both teens and adults, we found that insomnia and shortened sleep may lead to elevated stress, hormone levels and inflammation. These problems tend to show up before you develop heart disease.
