Seems logical as smoking affects the efficiency of the blood supply. If you smoke and/or drink alcohol your erection will be impaired to some extant. And, for all who say it's not a problem. How would one know without quitting smoking/drinking for a few months and comparing performance with past performance. Gotta have a base line I think. I sometimes wonder if my performance, hardly ever a complaint if I say so myself, would have been better and more pleasurable if I'd never started smoking. Just idle curiosity these days.Wonder how they're certain it's from smoking? I don't recall any headlines reading "Former Limp Dicks Report Stiffies Six Months After They Stopped Smoking".