Sleep problems ... to a painful cycle in which depression leads to sleep problems, which in turn worsen your depression. Depression, which doctors may call major depressive disorder, is a ...

such as drinking alcohol late at night, could be responsible for bad health outcomes, rather than the sleep cycle itself, he told CNN on Thursday.

Deep sleep refers to slow-wave sleep — a stage in the sleep cycle when brain waves slow down. Getting enough deep sleep is crucial for numerous bodily functions. But how to increase deep sleep ...