Smoking is a starting point for COPD, stroke, lung cancer, heart disease
In general, I think, people are aware that smoking is a major factor in lung disease, causing the overwhelming majority of chronic obstructive pulmonary disease (COPD, a combination of chronic bronchitis and emphysema), worsening asthma, and contributing to heart disease. In fact, smoking has been related to diseases of virtually every part of the body. A report by the U.S. Surgeon General in 2004 revealed that smoking has been linked to diseases like leukemia, cataracts, stomach cancer, cervical cancer, and cancer of the pancreas. Smoking also raises the risk of getting (and dying from) infectious diseases such as pneumonia and tuberculosis.
Smoking was first linked to lung cancer and cancer of the larynx in the 1960s, and later reports drew strong connections between smoking and cancer of the stomach and esophagus. In these cases, direct exposure to the smoke was the culprit: as inhaled smoke passes into the lungs, tissues in the mouth, throat, and airways are exposed to the toxins, and toxic exposure over many, many years and thousands of cigarettes was shown to be the cause. The later research concluded that swallowing smoke, which occurs as the smoker inhales, leads to exposure of the stomach and the esophagus (the tube that connects the mouth to the stomach), linking cancer of the organs to the toxic effects of smoking. Smoking also contributes to heartburn (gastro-esophageal reflux disease, or GERD), and it also interferes with the liver's ability to clear toxins.
Later studies linked smoking to heart and vascular diseases such as stroke and aneurysms. Part of this risk is due to the effects of nicotine, which raises the blood pressure, increasing stress on the heart and arteries. Smoking also causes changes in the make-up of the blood, making it more likely to clot, which may lead to stroke and myocardial infarction (heart attack). It is also likely that the toxins from smoke pass from the lungs and into the bloodstream, where all organs in the body are exposed.
Now, more information is available on the Internet about how smoking affects virtually every organ in the body. And recently, an article in the prestigious New England Journal of Medicine surveyed the risks associated with smoking among people in India. In the report, smoking doubled the risk of premature death from a wide variety of causes. In addition to deaths from heart disease, lung disease and vascular disease, smoking also increased chances of dying from tuberculosis and other infections and stomach ulcers. Since stomach ulcers are frequently caused by the bacteria Helicobacter pylori, it is possible that some of the danger from smoking results from a weakened immune system, which makes the body more susceptible to infection. It is still not clear how smoking weakens immunity, though some research has been done in the area.
Thus it is clear that smoking results in exposure of the entire body and all of its systems to toxins, which increases the risk of a wide variety of diseases. Depending on the disease, a smoker's risk is anywhere from 30% to 200% greater.
In future discussions, I will touch on many of the diseases mentioned here individually and more in depth. Until next time!