How do clear contacts effect vision negatively?

I was thinking about getting contacts and i've had a lot of negative and positive feedback from people who wear them daily... many say that wearing contacts increases power is it true?How do clear contacts effect vision negatively?
I have worn contacts for years and I love them! i have very poor eyesight, and i have noticed that my vision WITH contacts is much clearer and sharper than just wearing glasses. Plus i do not like glasses. they slide around and fog up and are a pretty huge hassle. the only problem i sometimes have with contacts is if i accidentally fall asleep in them. But otherwise i absolutely love them! They do not hurt and you feel like you actually have good eyes while they're in lol. u can ask me any questions you may have but i will highly reccommend them!





As for affecting vision negatively, they don't. I have had the same vision for maybe 7 or 8 years now wearing contacts the entire time. and i'm not sure what you mean by increasing power, however just contacts themselves do not actually change your vision in any way.