Bah!!!!! Smoking is not a good thing for anyone, but whether it actually causes disease is a big ? in my book.
IMO, since so many people smoke or have smoked, and so many people have contracted cancer, heart trouble, MS and more, it's a no brainer to come up with..aha, smoking must cause these illnesses.
The thing that tics me off is, these studies cost multi bucks that could be used to find a cure for these illnesses.
There are many causes and triggers for many illnesses, and if we stopped doing all the things that
may cause disease, we would die of starvation or live the rest of our lives in gas masks.
I've smoked since I was 19 (at least a pack per day) and today my lungs are clear, my heart is normal, my blood pressure is normal, as well as all my vitals, and I'm 69..

....Knocking vigorously on wood and praying not to be struck by lightening, as I sit here.
Oh and Trish, I'm only vaping nicotine, now....but, who knows, next, they will find it causes disease too. Damned if you do, damned if you don't.
News Flash...We're all gonna die!!!