"It gets the tummy back quicker," she said. "People don't gain weight with breastfeeding unless they eat an excessive amount of food," she said.
Still, it takes time to lose the baby fat and lactation experts recommend losing no more than one to two pounds a week.
"A crash diet of 800 calories a week is not normal," said Clark. "People may tease you because you don't look like a movie star. But she had a personal chef, a nanny and trainer every day. Most physicians won't let you go back to the gym right away and it's even longer for a C-section (caesarean section)."
Meanwhile, actress Hayek is looking as beautiful as ever, despite claims of weight gain. In an interview with television's "Extra," she said her daughter's birth had changed her life.
"I don't even remember what my life was like before," she said. "I can tell you that I don't sleep. This is a cliché but it's true. I haven't slept in the last six months."
"The blessing of having a healthy child," said Hayek, "I think is the best thing that can happen to anyone."