Here's a few things to consider (just my 2 cebts worth, anyway)
Nicotine is a vasoconstrictor. It inhibits circulation, therefore it has to inhibit your body's ability to absorb nutrients...
Nicotine is believed to be more physiologically and mentally addictive than heroine, cocaine or alcohol.
I used to LOVE smoking some good green bud and then having a few cigarettes to enhance the buzz. I quit smoking weed altogether a long, long time ago - I guess it just got old - I didn't get old, getting stoned did. When I quit, I just quit. It was easy.
I kept smoking cigarettes for about 4 years after I gave up pot. I think I somehow associated cigarettes with the buzz I used to get from weed and got into smoking about 1/2 pack a day.
My dad's an ex-smoker. He never had another cigarette after his funeral a few years ago (he died from cardiovascular disease caused by cigarettes). I gave up smoking a few months after we buried him.
If you can quit now, you should. 'Nuff said.