When Mad Men actor Hamm was just 20, he experienced chronic depression following his father's death. The structured environment of work and school (he was a college student at the time) helped him recover, but he also relied on therapy and antidepressants to pull him out of a downward spiral.
"You can change your brain chemistry enough to think: 'I want to get up in the morning; I don't want to sleep until four in the afternoon," Hamm told UK magazine The Observer in September, 2010, speaking about medication.
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Today she has a loving husband, a successful acting career, and a passion for humanitarian work, but life was not always so picture-perfect for Judd.
In her 2011 memoir, All That Is Bitter & Sweet she revealed that she considered suicide as a sixth-grader, and in 2006 underwent 42 days in a rehab clinic for depression. "I would have died without it," she told People in April 2011. Reconciling with estranged family members and helping those less fortunate through charity work has helped Judd regain perspective and make peace with her past.
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His public persona is that of a laid-back, fun-loving dude, but the world saw a darker side of the actor in 2007 when reports surfaced that he had attempted suicide at his California home. Some friends were shocked, but others said that Wilson, who was 38 at the time, had "battled his share of demons, which have included drug addiction," reported People.
Wilson "bounced back" from his suicide attempt, People reported eleven weeks later, by spending time with family and close friends.
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When model and actress Porizkova was voted off ABC's Dancing with the Stars in 2007, her feelings of rejection led to anxiety attacks. An antidepressant helped dull her anxiety, Porizkova wrote in a 2011 Huffington Post editorial, but also her personality.
She eventually stopped the medication, fighting withdrawal symptoms with exercise and willpower. While she's not an "anti-medicine crusader," she wrote that she is "starting to wonder whether antidepressants can often be the emotional equivalent of plastic surgery."
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The whole truth behind Ledger's tragic death in January 2008 will likely never be known: The troubled actor, 28, accidentally overdosed on sleeping pills, painkillers, and anxiety drugs not long after revealing to the New York Times that he'd been suffering from insomnia.
After his death, People reported that sources spoke of his depression and reckless behavior after his breakup with actress Michelle Williams, the mother of his then 2-year-old daughter.
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Disney actress and singer Lovato made headlines in 2010 by checking into a treatment facility for "emotional and physical issues" after being involved in an altercation with a dancer on the Jonas Brothers World Tour.
After leaving the center and getting her life back under control, Lovato revealed to People that she suffered from anorexia, bulimia, and bipolar disorder. She says that "looking back it makes sense. There were times when I was so manic, I was writing seven songs in one night and I'd be up until 5:30 in the morning."
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After Arquette and wife Courteney Cox announced they were separating in late 2010, the actor was spotted dancing and behaving erratically at nightclubs. He told Howard Stern during a radio interview that he'd been drinking a lot and acting like a "maniac."
Arquette soon checked himself into a rehab center to address his alcohol abuse and depression. In April 2011, Arquette acknowledged his strange behavior, saying he had been sober for more than 100 days and was now more in touch with his emotions.
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In 2011 actress Zeta-Jones, 41, revealed that she has bipolar II disorder, which causes severe depression. (People with bipolar II often don't have the extreme "up" of mania, which is a staple of bipolar I.)
Dateline NBC host Jane Pauley praised Zeta-Jones' decision to go public, saying that "she has made the world a safer place for people who have the diagnosis." Pauley, 60, was diagnosed with bipolar disorder in 2001 and wrote about her experience in her 2004 memoir, "Skywriting: A Life Out of the Blue."
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Former NFL player Andre Waters shocked family and friends in November, 2006 when he took his own life at age 44. Posthumous studies suggest he'd been suffering from brain damage and depression, both related to concussions sustained during football games.
Since then, more than a dozen football-player deaths have been linked to this condition, known as chronic traumatic encephalopathy, or CTE. Fellow ex-football star Dave Duerson, 50, also committed suicide in 2011. Duerson believed that he was suffering from CTE as well.
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Actress Paltrow loved being a new mom to daughter Apple, born in 2004. When her son Moses was born two years later, however, something was different.
"I felt like a zombie," Paltrow told Good Housekeeping in February 2011. "I couldn't access my emotions." Still, she didn't suspect postpartum depression until her husband brought up the idea. "I thought postpartum depression meant you were sobbing every single day and incapable of looking after a child," she said. "But there are different shades and depths of it."
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Marissa Jaret Winokur
Postpartum depression isn't reserved for women who physically give birth to their children. After Tony-winning Broadway actress Winokur's son was born via surrogate in 2008, she felt stressed and overwhelmed.
In fact, surrogacy can sometimes make postpartum anxiety or guilt even worse, Winokur's doctor told People in December 2010. "I didn't feel a connection with Zev," Winokur said.
She visited a therapist, went back to work, and started exercising, and her depression began to lift when her son was about 10 months old.
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Winning gold at the 1996 Atlanta Olympic Games forced swimmer Beard, then only 14, to grow up fast. But when a growth spurt and 25-pound weight gain caused Beard's self-esteem to take a dive, the self-proclaimed perfectionist turned to bulimia and cutting herself as an outlet for her pain and depression.
Beard began taking antidepressants in 2005, which helped her get healthier. Today, she's off medication and has a son, born in 2009, but admits that life still isn't perfect. "It's not like I went to therapy andpoof!better," she told People in 2010.
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Jeret "Speedy" Peterson
Olympic freestyle skier Peterson lost his long-time battle with depression in 2011 when he died of a self-inflicted gunshot wound at age 29.
Peterson won a silver medal at the 2010 Winter Games, but had fought depression and gambling, and had struggled to stay sober for years, reported People. He discovered skiing during his troubled childhood, and used it as a way to burn off "ADD hellion" energy otherwise spent causing trouble, reported Men's Journal in a 2010 profile on Peterson.
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Before Kate Middleton married England's Prince William in 2011, she received counseling to prepare herself for life with the royal family, according to the Daily Mail. The counseling was likely meant to be preventive: William's mother, Diana, after all, had experienced loneliness and depression in her role as a prince's wife.
Diana suffered from postpartum depression as well as an eating disorder. According to the BBC, her unhappiness worsened as her marriage fell apart, and she received little emotional support from her new family.
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"I know how important good mental health care can be because I personally benefited from it," wrote Gore, the now-estranged wife of Al Gore, in a 1999 USA Todayopinion piece. In the article, Gore revealed that she had sought depression treatment years before, after her son had a near-fatal accident. She took medication for some time. "When you get to this point," she said in an interview, "you just can't will your way out of that or pray your way out of that or pull yourself up by the bootstraps out of that. You really have to go and get help, and I did."
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The actor best known for his role as "Boner" on the 1990s sitcom "Growing Pains" battled depression for most of his life. That's what Koenig's father told reporters in February 2010, shortly after Koenig took his own life. According to Koenig's sister, he had recently stopped taking his medication. Koenig's parents have been outspoken about their son's depression, hoping that their message may be able to reach others who are also considering suicide.
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Model and actress Shields was one of the first and most prominent celebrities to speak openly about her struggle with postpartum depression. She wrote about it in her 2005 book, "Down Came the Rain: My Journey Through Postpartum Depression."
Shields published an opinion piece in the New York Times, defending her decision to take medication and describing the outpouring of support she'd received from other mothers who'd been in the same position.
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As host of ABC's "Extreme Makeover: Home Edition" from 2004 to 2009, Hemmis was bubbly, compassionate, and always smiling for the camera. But in September 2009, the carpenter and entrepreneur opened up to People about her ongoing struggle with depression that had caused crying fits, eating binges, and insomnia early on in the show's run.
While working on a show like "Extreme Makeover"which restores and refurbishes damaged or destroyed homes for families in needis both rewarding and fulfilling, it was also emotionally draining at times, Hemmis said.
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Starring in and executive-producing the 1999 feature film "Girl, Interrupted"about a young woman's two-week experience in a psychiatric wardwas deeply personal for Ryder. After her high-profile relationship with actor Johnny Depp ended, Ryder, then 19, began abusing alcohol, experiencing anxiety attacks, and spiraling into depression, she told the San Francisco Chronicle in January 2000. After falling asleep with a lit cigarette and setting herself on fire, Ryder sought treatment, briefly, in a mental institution herself, and finally with a private therapist.
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Former Playboy Playmate and reality TV star Wilkinson's life changed dramatically after she had a baby at 24. "I felt like I had to be a different person," Wilkinson told People. "I was doing whatever I could for the baby, but I lost myself and it was really frustrating."
Pressure to regain her famous figure didn't help, and she was depressed for some time. Two years later, happy and healthy again, Wilkinson spoke openly about her postpartum depression, saying that it affects many women and that "it needs to be talked about."