Kelly Clarkson says her weight is a physical reflection of her emotional state.
"It's when I'm fat that I'm happy," Clarkson told the magazine.
"People think, 'Oh, there's something wrong with her. She's putting on weight.' I'm like, 'Oh, no!' I'm sorry, but that represents happiness in my emotional world.'"
"For me, when I'm skinny is usually when I'm not doing well," she said.
"If you gauge your life on what other people think, you're going to be in a constant state of panic trying to please everyone. People should just concentrate on their own lives and their own health and their own happiness."Clarkson said she also faces criticism when she loses weight, making it impossible to win over everyone.
She and fellow singer Miranda Lambert have commiserated over the public's warring opinions about their appearance.
"Same thing happened with Miranda Lambert -- I had dinner with her and we were talking about that. She was like, 'Should I gain? Should I lose?' But no one actually cares about your health."
Clarkson previously told Attitude magazine that people didn't realize she was "miserable" for years because she was thin.
She said she was skinny because she was at the gym "all the time" to deal with her unhappiness.
"When I was really skinny, I wanted to kill myself," the singer confessed.
"I was miserable, like inside and out, for four years of my life. But no one cared, because aesthetically you make sense."