Where exactly did you "hear" that? Probably from the same source that says "You know what "they" say...LOL
Be careful what you expose yourself to. p 0 r n is addicting and destructive...and will destructive to your relationships. It sets an unrealistic idea of sex...expectations and images in your mind. It will be difficult not to compare your mate to these images that you've placed in your head.
I know, I know...and I'm quite sure you will get people responding in this forum who will tell you it is perfectly fine and to go for it....well, it is not fine and you will regret it...especially after a few years of unsuccessful unfulfilling relationships.
Stop now. It doesn't really matter what others are doing.