People often think they’re depressed when they’re sad, or sad when they’re depressed. It’s easy to confuse the two, since both states are largely characterized by a dip in mood. “It’s by no means the only feature, but we do associate depression with a sad mood,” says Guy Winch, a New York City-based psychologist and author of Emotional First Aid: Healing Rejection, Guilt, Failure, and Other Everyday Hurts. “But they’re not the same.”
Sure, at one time or another you might dramatically proclaim that you’re depressed after screwing up a relationship or disappointing your boss—but how can you distinguish typical sadness from the more serious beast? How can you tell if you’re just in a particular emotional state, or if you’re one of the 16.2 million US adults who live with depression each year?
First, think about the last time you felt sad. (Sorry to make you relive it.) What caused that feeling? Maybe a family member passed away, or a close friend made a remark that cut deep. Whatever it was, you probably felt sad about something. “Sadness is a normal human emotion,” says Marwa Azab, an adjunct professor of psychology at California State University, Long Beach. “It’s a healthy response to any kind of loss, disappointing outcome, or hurtful comment.”
Sadness can come and go quickly; it usually fades once you get over whatever put you in that funk in the first place. But depression can taint your mood and other aspects of your life for seemingly no reason—and it lingers. “It’s a much more global experience,” Winch says. “It’s an abnormal emotional state that impacts our thoughts, feelings, perceptions, and behaviors. It does this in both subtle and overt ways.”
According to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), to be diagnosed with clinical depression you must experience either a sad, depressed mood or a loss of pleasure from things that used to bring you joy. On top of that, you have to have at least four other symptoms on the list, which include things like fatigue, lack of concentration, too much or too little sleep, suicidal thoughts, changes in appetite or weight, and slowed movements or speech. If you experience these symptoms for at least two weeks, depression is more likely to be diagnosed.
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Each person wears the illness differently. You might cry all day or feel nothing at all. “It’s like a gray filter has formed over our vision so that all the colors and vibrancy in our lives get sucked away,” Winch says. “We’re left with this bland vision of the world in which we feel unengaged and uninterested in the things we used to care about.”
Certain factors increase your risk of depression, like genetics—one recent study found that your risk doubles if one of your parents has been depressed. Your chances also creep up if you’ve lived through abuse, violence, or poverty, or if you have a pessimistic outlook or low self-esteem.
There’s also a difference between sadness and depression on a neurological level. In the brains of depressed people, less blood flows to the attention network and more blood flows to the amygdala, the brain’s fear center, Azab says. “So it’s not surprising that a person with depression might be much more focused on the negative, because the fear center is hyper-activated,” she says.
Chemical imbalances can also explain the symptoms to a certain extent, she adds. Depression is linked to lower levels of serotonin, which regulate sleep; dopamine, which controls the brain’s reward and pleasure centers; and epinephrine, aka adrenaline, which is involved in the body’s fight or flight response.
You need to see a therapist or medical professional to get a legitimate diagnosis—never a bad idea, considering therapy is one of the most common treatments for depression. Another option: antidepressants, and if all else fails, electroconvulsive therapy. (Much less barbaric now than it was in One Flew Over the Cuckoo’s Nest.)
Never ignore suicidal thoughts, but if your symptoms are relatively mild and you’re on the fence about getting help, you can take some steps on your own to see if your mood improves after a week or two, Winch says.
Winch suggests doing cardio four times per week (it’s a hotly contested question, but research does show it helps with depressive symptoms and can even prevent future episodes). He also advises participating in activities that you once enjoyed—like cooking or just meeting up with friends—even if you feel like doing anything but.
Whatever you do, don’t stay in your pajamas and mope around the house all day. “It’s the worst thing you can do for yourself because there’s a negative mental state that goes with it,” says Winch, whose TED Talk explains the importance of “emotional hygiene.”
Azab suggests adopting a healthy diet, trying to get seven to eight hours of sleep per night, and working to mitigate psychological factors like job dissatisfaction and toxic people (easier said than done, of course). If after a week or two none of these changes reflects positively on your mood, schedule an appointment with a doctor or therapist.
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