How Sally Field Gained 25 Pounds To Transform Into The First Lady For 'Lincoln'

It doesn't look like Sally Field went through much of a transformation to become the first lady in "Lincoln"; however, the 66-year-old actress gained 25 pounds for the role.

Though Field says she was already the same height as Mary Todd, during a new 20-minute mini-documentary for the film, the actress mentions that she gained the weight to fit Mrs. Lincoln's measurements.

On "The Tonight Show with Jay Leno," Field shared it wasn't a fun feat.

"I tried to do it healthy, which I understand there isn't any way to do it healthy," she said. "I ate brown rice and these protein drinks made out of stuff called pro-Gain . . . Oh God, it was just disgusting. I never had a fun meal, basically. It just was discipline."

Field told Leno it took her nearly six months to gain the 25 pounds, and another year to lose it.

"I began to work out like a mad fiend. I had two trainers. I really worked out hard 4 times a week," said Field. "I eventually had to have knee surgery. My little frame couldn't hold this amount of weight."

Nearly all of the costumes Field wore in the film are near exact replicas of clothes found in paintings or photographs of the first lady.

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