<human>: Can you provide a brief overview of the text?

While I was getting a check-up at my local doctor's office, the M.D. noticed I had some irritation on my throat, and asked if I smoked. I responded "no tobacco, but marijuana." Then my mother interrupted our conversation abruptly by saying "Can you please tell him that marijuana is just as bad for you lungs as tobacco!" I responded rather quickly with "No mom, there is no evidence you have to support that." So after a long chat the ONLY thing the M.D. could say was that marijuana's psychological effects can cause an artery to spasm, which can lead to a panic or heart attack, but "not likely," he assured. My mom says that she wants full-on tested proof and facts in order to prove to her that tobacco is way worse that marijuana, and that it has no harmful effects, except maybe lowering lung capacity.
<bot>: My mom says pot is just as harmful as tobacco, need to show her proof that it is simply not true and that pot is not harmful.