How does tobacco smoking affect someones breathing rate?

Nicotine and other chemicals in the smoke constrict blood vessels throughout the body. Blood and oxygen can't move as easily through narrowed blood vessels, increasing the likelihood of Heart disease or stroke. The poor circulation can also make a smoker's fingers and hands cold.

When a smoker inhales cigarette smoke, these chemicals enter the bloodstream and reach the brain in less than 10 seconds. It takes only 15 to 20 seconds for nicotine to reach every part of a smoker's body. At this speed, the effects of tobacco are felt almost instantly.

it slows the flow of oxygen throughout the body.