In a recent interview Lady Gaga said she had done various kinds of drugs. In particular, she felt that she became addicted to marijuana. She said she's ready to quit and show the world that she can be just as creative without them.

Gaga admitted that she has been addicted to "various things" over the years but mostly used pot to self medicate herself both physically and mentally.

She says she's ready to give it up. Not only for her personal health but also to prove that she can be just as creative without them.

It seems she's afraid of not living past the age of 27. Of course she's referring to the curse of the 27 year old musicians who all passed away at that age because of drug use.

[Source]