Jennifer Lopez partly owes her post-baby body to a meal delivery service, which limits her calorie intake.
The 40 year old shed 50 pounds (22.6 kilograms) after giving birth to twins Max and Emme in February 2008 - and she has kept the weight off.
Lopez's trainer Gunnar Peterson insists the Latina's work ethic helps her stay fit and lean, but her diet really works.
Peterson tells Life & Style magazine that Lopez has been using the meal delivery service Freshology since October 2008. The diet keeps her to no more than 1,400 calories a day.
He says, "She stays ready so she doesn't ever have to get ready."