It's not as odd as it sounds—and it's not always such a bad thing either. Here's what our gray moods may be telling us.

There are days when Ashley, 30, feels like her life couldn’t be better. She excels at her flex time job as creative director of an e-learning company based in Nashville, leaving her enough hours in the week to revise a YA novel she’s been working on. (“I feel good when I create, and I really want to be a published author,” she says.) Married just a few months ago, she has a thriving social life, hitting the city’s restaurants and bars with her husband and their friends and joining a workout buddy for regular Zumba classes.

Then there are the times when all the unrealized aspects of Ashley’s life dominate her thoughts: the unfinished novel. The old paint job on their house. The small things that went wrong at the wedding (including a deejay who forgot to load her playlist). “I get progressively more upset as I think about them,” she says. Sometimes, she can’t even muster the energy to get out of her pajamas and spends a whole day on the couch “being unproductive and feeling sorry for myself.”

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Joy and despondency tag-team in Ashley’s life in a way that might seem contradictory. But her experience is hardly unusual. “People who say they’re happy are generally less likely to also report feelings of depression, but that correlation is far from perfect,” says Jean Twenge, Ph.D., professor of psychology at San Diego State University and author of Generation Me: Why Today’s Young Americans Are More Confident, Assertive, Entitled—and More Miserable Than Ever Before. “Certainly, some do experience both.”

Young women may be most prone to this apparent paradox. A Pew Research Center poll from 2010 found that young adults are more likely than older ones to report a happy mind-set, with 31 percent identifying as “very happy” and an additional 56 percent as “somewhat happy.” But they also show more symptoms of depression than do previous generations. A 2014 study authored by Twenge in the journal Social Indicators Research found that, since 2000, young Americans have reported substantially higher levels of depressive symptoms than those in the ’80s and ’90s, including negative feelings, sleep disruption and poor concentration. The trend was magnified in females, who are nearly twice as likely as males to have clinical depression. The Mayo Clinic reports that one in five women will develop depression in her lifetime. “The data suggests that women ruminate more about failures,” explains Emiliana Simon-Thomas, Ph.D., science director of the Greater Good Science Center at the University of California in Berkeley. And that sort of obsessive stewing may lead to depressive symptoms.

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True Blue?
It’s not unusual to moan, “I’m so depressed!” after a bad day. But as the American Psychiatric Association defines it, depression is a disorder with a clear-cut list of symptoms. These include taking little interest or pleasure in doing things, feeling down or worthless, sleeping too much or too little, feeling tired and having trouble concentrating. (For an adapted version of the list, called the Patient Health Questionnaire, google “PHQ-9.”) Experiencing more than a couple of the symptoms on the APA’s list daily (or almost daily) for at least two weeks may predict a diagnosis.

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Happiness, meanwhile, is both an emotion and a subjective judgment about life. Happiness and life-satisfaction questionnaires administered by psychologists ask things like “Is your life close to ideal?” and “Do you have the important things you want?” And so, while happiness and depressive symptoms typically move in opposite directions (the more you have of one, the less you have of the other), they can also float up or down in tandem, because they reflect different things. For example, you can be dissatisfied with your life yet still feel energetic and upbeat. Or you can be generally happy with your circumstances, yet your mood can be lousy.

Like many other disorders, clinical depression falls on a continuum, from mild to moderate to severe. A mildly depressed person might feel badly a lot of the time but manage to keep up appearances, whereas a severely depressed person often can’t drag herself out of bed. But if sadness strikes only once in a while, and if it never keeps you from your morning meetings or your best friend’s birthday party, experts call it something else: “Totally normal,” says Jackie Gollan, Ph.D., associate professor of psychiatry and behavioral science at Northwestern University’s Feinberg School of Medicine. Especially if you’re grieving or recently had a bad breakup, though the feelings might also stem from small issues, like missing your family, disliking your job or having an argument.

These fleeting blue moods can occur within a broader experience of well-being. “A wide range of research shows that people feel mildly happy most of the time,” says Robert Biswas-Diener, psychologist and author of The Upside of Your Dark Side. “It’s our natural resting place.”

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That pretty well describes Marlo, an athletic, 30-year-old sports marketer in Los Angeles, who occasionally spends evenings at home feeling melancholy, sipping whiskey and listening to country music by George Strait. “It reminds me of where I grew up,” she explains, on a farm in a small town in the Deep South, where her parents still live. She misses them and her friends who stayed home, marrying young and having babies. Marlo, meanwhile, is still looking for a mate. “Guys in L.A. are impossible,” she says.

Her work typically makes her troubles worthwhile—it’s taken her to three Olympics. Still, whenever there’s a lull or a tough week, “I have to find ways to deal,” she says. After one breakup, she took up boxing. “I’d call my trainer and tell him I was about to cry, and he’d say, ‘Come over and box,'” she says. “I’d get out all this anger and aggression and sadness.”

Though many of us can naturally find our way back to our happiness set point, sometimes our built-in coping mechanisms can’t quite keep up with circumstance.

Katherine, 25, is an analyst with an energy company in her hometown of San Antonio. It isn’t her dream job; she loves fashion and travel. But she saw many of her fellow MBAs struggling to find work and felt lucky for the experience and solid pay. She’s been putting in up to 12 hours of daily toil ever since, squeezing in exercise and friends.

About six months into her job, she started laboring to get out of bed. She was plagued by dissatisfaction with her job, the frustration and disappointment from “settling” and anxiety about her work performance, she says. (Anxiety and depression often go together, Twenge notes.)

One day last spring, a routine work phone call set off a full-blown panic attack. “I felt really shaky, like my heart rate was really fast and I couldn’t breathe,” Katherine says. She started crying and fled to the company nurse’s office, where she lay in a dark room until she recovered. “It was uncontrollable and totally embarrassing,” she says. “That was when I realized this isn’t normal, and I went to see a counselor.”

The counselor screened her for depression. “I was somewhere in the middle, not completely depressed, but not in a good place either,” Katherine says; she subsequently visited a psychiatrist, who prescribed a small dose of Zoloft. “It helps control the emotions that were making it hard for me to go to work.” The counselor also offered tactics to help her manage her moods. “She had me write in a diary every day things that I was grateful for,” Katherine explains. “So I wasn’t writing ‘Crappy city. Boring job. My life sucks.’ I was grateful for my family and all the opportunities I’ve had.”

Perfection Problem
Ironically, the very habits that help women become super successful may also lead to depression. We have lofty goals, but we may feel disappointed if we don’t reach them. Or we do what others expect of us. “I call it ‘shoulding’ on ourselves,” says Christine Carter, Ph.D., sociologist and author of The Sweet Spot: How to Find Your Groove at Work and at Home.

And while perfectionism might make us good students, employees and entrepreneurs, it also correlates with depression. Multiple studies by Paul Hewitt, Ph.D., professor of psychology at the University of British Columbia, found that people who strive to be flawless are significantly more vulnerable to depressive symptoms. “I’m a total type A personality,” Katherine admits. “I don’t like to make mistakes.”

Add to that our culture of overwork. A study of 2,000-plus white-collar employees found that those who regularly work 11 or more hours a day had more than twice the risk of becoming depressed. Technology compounds the problem. “It’s created the expectation that we are available 24/7,” Carter says. “It’s impossible to enjoy your life and feel profoundly, truly joyful if you don’t give yourself time to rest. Even social media, which allows us to connect with more people, has been shown to impact well-being, not least because it taunts us with perfect, airbrushed versions of others’ lives.”

And while it’s great that individuals can strike out on their own, finding jobs in new cities or starting families by themselves, a solo lifestyle can increase loneliness, which is also linked to depression. “We’re tribal, cave people,” Carter says. “If you’re spending the majority of your day alone, it doesn’t feel good to most people. There’s a little part of your nervous system wondering where your clan is.”

Rachel, who lives by herself in the Houston area, is an ob/gyn resident at 26. “I did college in three years and didn’t take any breaks because I wanted to move forward faster,” she says. She treats patients and scrubs in and out of surgery for 80 hours a week, then often comes home at 9 p.m. Sometimes she’ll call around to see if any friends can grab dinner, but they’re usually too busy with their partners or new babies. So she’ll play her guitar or go for a run to keep from feeling bad. “I feel it most when I’m not busy,” she says.

Alone at home, she’ll ruminate on how she’ll be able to find a partner and start a family, given the intensity of her job: “I should feel satisfied because things are going well. I’m making more money than before, and nothing in particular is wrong, so why do I feel bummed? I probably should see a counselor, but I don’t have the time. I tell myself I don’t have this diagnosis because I don’t want it.”

It’s difficult to take on the stigma of mental troubles, which is why the women interviewed for this article asked to be identified only by their first name.

Silver Linings
Bad moods, though unpleasant, are not necessarily a bad thing. Research shows that people in negative moods are better negotiators and less gullible. They’re more aware of threats and take fewer risks. An angry mood can boost performance in competition. In important ways, negative feelings can contribute to our success.

One hundred percent happiness should never be the goal anyway, says Biswas-Diener. “Sometimes the appropriate emotional response is to be guilty or jealous or angry or sad.” Each mood is normal and serves a valuable purpose. Guilt means you’ve violated your own moral code, while sadness means something important is missing. “Think of your moods as a thermometer that takes the temperature of your life,” he says. “If you just want to be happy all the time, it’s like wanting to break your thermometer.”

Of course, no one wants to live under a gray cloud. Biswas-Diener suggests we aim for an 80:20 ratio of positive to negative emotions. “A 50:50 ratio is probably not good enough. All that emotional distress is telling you that the circumstances of your life need attention,” he says.

Rather than running from bad moods or drowning them in work busyness, listen to your feelings. “What are they telling you?” asks Biswas-Diener. Doing so “starts to undercut their negative impact,” he says. And it may lead you to think of creative solutions for the underlying problems. Ashley, the would-be YA novelist, has begun to use this tactic when she is ambushed by negativity. “Actually looking at it makes it easier to deal with than pushing it away,” she says.

You can push back against occasional sad feelings in other proven ways. Add activities and people to your life that make you feel competent and give you pleasure, Gollan says. Go for a hike, do volunteer work, or join a book club. “Exercise is the second thing I recommend. Figure out how to add more steps per day to increase your energy level and stamina,” she continues. A recent Swedish study suggests that exercise causes muscles to produce an enzyme that protects the brain from depressed feelings.

Seek social and emotional support, another tactic shown to ward off depression. “My grandma doesn’t have Facebook, and she and I write letters all the time. And I actually have to call her on the phone and talk to her. I love that,” Katherine says.

If a screening suggests symptoms of depression, talk to your primary care physician, Gollan says. “Ask if you should be referred to a psychologist or psychiatrist. Mild depression can be tackled by behavioral approaches. Moderate to severe might also need medication. State-of-the-art care is really both.”

If instead your blues are garden-variety, take heart. You’re human. Put on a pot of tea and your favorite moody playlist. Acknowledge your sadness. Use it to make a few tweaks to your life. Then allow the bad mood to pass like a dreary winter day, leaving clear sky in its wake.