Scrutiny is going to come to pot consumption. Use-over-time does, according to initial studies, effect intelligence. It’s early studies, but the memory impairment seems set-in-stone. It does actually demonstrate that the brain is dramatically changed by usage. Currently, scientists don’t have a great deal of research yet, and I really feel that that’s an important step in the legalization process.
The short version is that high usage is not good for you. As in all things, Moderation is key.