But you must be patient and stay smokefree for three and more years. After that, health begins to rise, according to a study from Pomerania, Germany. The researchers have measured smoking cessation and the risk of being hospitalized in a sample of more than four thousand adults. - (Picture by timothyjohnhulme @ Flickr)
And why is there no short-term effect of quitting? Because the main reason for a smoker to quit is his doctor telling him he must, because he has found something bad: Quitting and entering a hospital may have a common cause in the short run. I would gess that the rise of health begins at the very day you quit smoking. But the success may be masked by the reason that causes you to quit. Anyway, better you do it today than tomorrow.