May 05

The Physiology of Smoking

There are four distinct phases of change that the body experiences during the process of smoking. By understanding these physiology changes a smoker can better appreciate the importance of the various Healthy Smoker strategies.

Phase One – Inhaling tobacco smoke causes nicotine to enter the bloodstream and go immediately to the brain. Once in the brain nicotine stimulates the release of seratonin and dopamine neurotransmitters, which provides the “good feelings” of relaxation or even excitement. The receptor cells in the brain that receive these neurotransmitters soon become less sensitive to this stimulation. This requires higher and higher doses of nicotine to produce the same level of stimulation.

Phase Two – Very shortly after nicotine reaches the brain it also reaches the liver, which triggers the release of sugar into the bloodstream. The added sugar produces a feeling of energy for the smoker, which combined with the feel good sensation in the brain gives the smoker an overall feeling of energy and concentration. These sensations are very temporary because they are chemically stimulated rather than being produced by nutrients that are more sustainable.

Phase Three – Due to the release of sugar into the bloodstream the pancreas reacts to release insulin needed to help deliver sugar to the cells as well as keep sugar levels balanced in the body. Sugar levels are temporary and excess insulin results since the pancreas thought real food was the cause of the increased sugar levels. This causes sugar levels to drop lower than they were before the cigarette. At the same time neurotransmitter release also stops because it was also short term. This combination of stalled neurotransmitter release and low blood sugar produces feelings of fatigue, irritability, hunger, and craving for another cigarette. This cycle usually takes about 15 minutes.

Phase Four – As blood sugar and neurotransmitter levels are falling nicotine stimulates the nervous system to release adrenaline into the body. This causes increased heart rate and respiration as well as feeling of tension which combined with the feelings of fatigue and craving causes the desire for another cigarette. This is precisely how the body reaches a state of addiction.

This cycle interrupts regular eating patterns which in turn causes the body to experience imbalances due to nutritional deficiencies. Chemicals take up residence in the cells of body as antioxidants lose their ability to neutralize the excessive free radicals being consumed. The cells, in an effort to protect themselves, surround themselves with cholesterol causing the cell membrane to become harder and less subtle. This restricts the ability of cells to take in nutrients and excrete waste products, which weakens cells. The cells begin to age prematurely and become vulnerable to illness and disease.

© Charles K. Bens, Ph. D