Jim Parsons says starring as Sheldon Cooper on The Big Bang Theory brought enormous success—but behind the scenes, he was often miserable. Appearing on the All Out with Jon Dean podcast, the actor said that despite being at the peak of his career, he was constantly stressed and unhappy during much of the show's 12-season run. Parsons admitted he put tremendous pressure on himself, describing his work habits as obsessive and saying he believed he had to keep "all the plates spinning" to maintain his success. Looking back, Parsons says he wouldn't put himself through that level of stress again, regardless of the paycheck. He also revealed that he was sober for the final nine years of the series and feels his obsessive approach caused him to miss out on many experiences in life. Now, Parsons says he has a healthier perspective on both his career and the lasting fame that came from playing Sheldon, calling celebrity "a very odd psychological thing" while acknowledging he's learned to embrace it in a much healthier way.