For her last movie called “Eat, Pray, Love (Ye, Dua Et, Sev)”, Julia Roberts had to gain some weight and she explained the way she chose for it was "eating pizza". Julia Roberts is known to be against the esthetic surgeries and it is now a mystery how she have made her breasts bigger.

Source: here

Hmm I have no idea if she had breast augumentation or simply put on weight but I know she looks way better this way

She simply put on weight... eating anything makes your breasts bigger. Pizza is pretty high on calories, that will do