The 26-year-old beauty said she has not been working out since having her son Noah but she has been able to get her body back, reported Daily Mail online.
"I am not eating dairy, that is my biggest secret. It is really hard on your hormones and it's not good. If you want to gain weight, eat dairy. If you don't, don't eat it," she said.
Fox gained 23 pounds while expecting her first child to husband Brain Austin Green.
"I only gained 23 pounds when I was pregnant and I'm still 10 pounds heavier, but I don't want to kill myself trying to get back into shape because it's not a priority right now. I'm too in love with Noah and I don't want to be away from him. I just want to be home," she added.