Directed by Glee's Ryan Murphy, the movie is based on the best-selling memoir by Elizabeth Gilbert.
At a press conference for the film in Bardessono hotel in California's Napa Valley, the 42-year-old beauty said she ate endlessly during the filming, reports People magazine.
'They did go to great elaborate pains to make great food that I had to eat. Endlessly eat -- in the heat,' People magazine quoted Roberts as saying.
'But it was delicious. Ryan [Murphy, the film's director] keeps telling people I gained 10 pounds,' quipped Roberts.
'It was a little less than that. And I loved every pound,' she said.
Between the pasta, pizza and other Italian delicacies, the endless stream of food did get a bit tiresome after a full day of filming.
So, did she swear off Italian for good since completing the film?
'Not a chance. '[I''ve eaten] tons, tons. It can't slow me down,' Roberts said.
The movie is slated for a release on August 13.