Most smokers perceive the immediate effect of smoking as something positive; a stimulant that makes them seem to feel more alert, clearheaded and able to focus on work. However, the smoker?s perception is mostly an illusion. Take a look at what smoke does to the brain.

Within ten seconds of the first inhalation, nicotine, a potent alkaloid, passes into the bloodstream, transits the barrier that protects the brain from most impurities, and begins to act on brain cells. Nicotine molecules fit like keys into the ?nicotinic? receptors on the surface of the brain?s neurons. In fact, nicotine fits the same ?keyholes? as one of the brain?s most important neurotransmitters (signal chemicals), acetycholine, which results in a rush of stimulation and an increase in the flow of blood to the brain.

After ten puffs have flowed through the lungs, the smoker feels energized and clearheaded, but this is partly due to the fact that this was a period which ended a nicotine depravation, and another is about to happen. Within 30 minutes, the nicotine is reduced and the smoker feels the energy slipping away. A second cigarette is lit, and there is another surge of adrenaline, but now there is a feeling of one of the paradoxes of smoking, that at one dose it can stimulate, at another soothe. The muscles throughout your body starts to relax, and your pain threshold rises.

Another 30 minutes pass and the attention of the smoker increasingly drifts away from work and toward the nearby pack of cigarettes. Nicotine prompts brain cells to grow many more nicotinic receptors which allow the brain to function normally despite an unnatural amount of acetylcholine-like chemical acting on it, so the smoker feels normal when nicotine floods the neurons and abnormal when it doesn't. ?You might say smokers live near the edge of a cliff,? says Jack Henningfield of the National Institute on Drug Abuse in Baltimore. ?Most are never more than a few hours away from the start of nicotine withdrawal symptoms.?

The American Psychiatric Association classifies smoking withdrawal as a ?nicotine-induced organic mental disorder,? and several studies have compared active smokers with ?deprived? smokers (those suffering nicotine withdrawal) on their ability to perform simple skill tests. These are often cited (and many were funded) by the tobacco industry as evidence that tobacco enhances alertness and performance. What they really show is that nicotine withdrawal causes dramatic mental dysfunction. Research revealed that a smoker might perform adequately at many jobs until the job gets complicated: a smoker could drive a car satisfactorily as long as everything was routine, but if a tire blew out at high speed he might not handle the job as well as a nonsmoker.

{?How Cigarettes Cloud the Brain,? Reader?s Digest, March 1995} In 1980, tobacco dependence was listed as a mental disorder in the official diagnostic reference for the American Psychiatric Association. In 1991, the Psychiatric Association reported that smokers have a higher lifetime frequency of substance abuse, severe depression and anxiety disorders involving aggression and antisocial behavior.

--------------------------------------------------------------------------------

The Pritikin Program states that smoking accelerates problems that come with old age, and shows up earlier in smokers, for example, premature osteoporosis. Smoking changes bone tissue, making it easier for minerals to leave the bone in solution. Smoking increases lung and bladder cancer. A smoker loses 26% of his field of vision. There is also hearing and visual impairment, taste impairment and general loss of physiological and mental function. It takes four to six days for the withdrawal symptoms to subside. After that, 90% of their problem is gone.

http://www.jrussellshealth.com/smoking.html