What does depression actually mean and how does it affect a person's health?

Depressive sxs: Mood isn't happy (i.e., sad, angry, irritable). It can lead to too much sleep or not enough sleep. Weight gain or weight loss. Energy level may be low or possibly even higher than normal if agitated. Depression makes one more succeptible to pain & vice versa. Depression can go hand in hand with problems like fibromyalgia. To make a diagnosis of major depression, sxs must last at least 2 weeks.