Jennifer Garner will not lose weight for movie roles.

The '13 Going On 30' actress claims she won't be taking on films which require drastic changes to her body because she hates calorie counting.

She revealed to Allure magazine: ''There were times I had to watch every calorie that went into my body. Doing something like that again ... it's not exactly on the top of my list.''

The mother-of-three - who has daughters Violet, seven, and Seraphina, four, and son Samuel, 17 months, with husband Ben Affleck - also insists she will never consider having Botox injections because she worries the cosmetic procedure would look too obvious.

When asked if she would ever have Botox, she joked: ''[No], because I have a big forehead and I don't want it to be like this slab, a big glacier.''

The 41-year-old star follows in the footsteps of fellow actress Gwyneth Paltrow, who has also sworn off Botox.

The 'Iron Man 3' star previously had fillers injected into her face but says the procedure made her look ''crazy''.

She said: ''I'll try anything. Except I won't do Botox again, because I looked crazy. I looked like Joan Rivers!''