Jennifer Aniston claims Justin Theroux will kill her if she ever has plastic surgery or Botox.

The 45-year-old actress feels under pressure to be ''ageless'' in Hollywood, but says her fiancé ''will put a gun to my head if I touch my face in any way.''

She said: ''I think, what I have been witness to, is seeing women trying to stay ageless with what they are doing to themselves. I am grateful to learn from their mistakes, because I am not injecting s**t into my face. I see them and my heart breaks. I think, 'Oh god if you only know how much older you look.' They are trying to stop the clock and all you can see is an insecure person who won't let themselves just age. I also have a fiancé who will put a gun to my head if I touch my face in any way.''

She added: ''I am fortunate enough to know women like Gloria Steinem, who I think is one of the most stunning women on the planet, and doesn't touch her face. Diane Keaton, Annette Bening, all of these fabulous fearless women who are flawless, they embrace it! To each their own--I don't judge it if you do it--but sometimes I wish I could beg the people I know, who I am very near and dear to, to not touch their face.''

But Jennifer admits she isn't entirely happy with her body and wants to lose five pounds.

The 'We're the Millers' star also told Yahoo! Beauty: ''These days, if I was being super picky, I would love to drop five pounds. That is just where I have always been really comfortable at about 110 to 113 pounds. But it is harder to get that down, at this age.''