Size two Jennifer Aniston has one of the most enviable figures in Hollywood thanks to a low-carb diet and plenty of exercise. Aniston will have 'pizza nights, burgers or Mexican food,' she told the outlet. Jennifer Aniston has one of the most enviable figures in Hollywood thanks to a low-carb diet and plenty of exercise. But once in a while the 56-year-old Morning Show actress likes to cheat on her diet. Last year Jennifer said she loves a 'cheat day' and will sip on a dirty martini cocktail when the mood takes her.