Jennifer Aniston believes Botox ''can really kick you in the a**.''

The 'Cake' star, who previously claimed her fiancé Justin Theroux would put a gun to her head if she tampered with her face in any way, admits she's still ''not a fan'' of the anti-aging treatment, as she sees a lot of ''bad plastic surgery and injections'' in Hollywood.

The 45-year-old actress said: ''People lose perspective. I look around and see how bad plastic surgery and injections can really kick you in the a**.''

Asked about her own beauty regime, the former 'Friends' star told the February issue of InStyle magazine: ''I just take care of my skin, eat well, exercise. And I love lasers and [other noninvasive treatments like] Thermage [radio frequency] and Ultherapy [ultrasound]. I also like a good micro-current facial.''

Jennifer is also a huge fan of ''everything from Chanel,'' fish oil supplements and probiotics, but believes that water and sleep are ultimately ''your best bets for really great skin.''

The actress loves working out and found it difficult to avoid the gym while filming her latest movie, in which she plays a woman who becomes addicted to painkillers.

She said: ''For two months there were no mirrors to look at, no manicurists. Nothing. The hardest part for me was when they said, 'Don't work out.' I said, 'But I have to.' And then I realised, Oh. When you're not working out, your levels of joy just go down, down, down. And it's not that easy to get the weight off once you stop working out. You say to your body, 'Hey, what's going on?' But that's just the 40s.''