The writers and performers of this song have repeatedly rejected the urban legend that this song refers to any sort of drug usage.  Peter Yarrow (of Peter, Paul, and Mary) has frequently explained that "Puff" is about the hardships of growing older and has no relationship to drug taking.  He has also said of the song, "it never had any meaning except the obvious one" and is about the "loss of innocence in children."

Thanks, guys, I appreciate you straightening that out!

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