How bad is smoke?

Hello all Today I went to an ENT specialist for a regular look in my nose and throat and such He asked me If I smoked, I said I smoke weed He then proceeds to tell me that smoking 1 joint is equivalent to a pack of cigarettes I didn't say anything, but after that I couldn't really get that out of my head I've been smoking and reading about cannabis for nearly 8 years dally Are there others who've heard this? It sounds like quack doctoring to me