"There's an epidemic in our country of girls and women feeling bad about themselves based on what .5 percent of the human race looks like," the Ghostbusters star, 45, says in the April issue of Redbook. "It starts very young. My message is that as long as everybody's healthy, enjoy and embrace whatever body type you have."
The comedian hopes her two daughters, Vivian, 8, and Georgette, 6, will never have to face criticism about their bodies.
"Give me your best punch in the face, and I'll take that punch, rather than have my kid feel bad about herself," she told the magazine.
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"A good portion of women in America are size 14 and higher. I just try to make clothing that'll make all women feel really good," said McCarthy.
"When I feel good about my clothes, I'm more patient with my kids. I don't beep at the guy in his car texting in front of me," said McCarthy. "I look at the world a little differently. The small happy moments add up. A little bit of joy goes a long way."