It is estimated that smoking tobacco products worldwide are associated with seven deaths every minute. Smoking is the leading cause of reversible disease in the United States, and it is linked to diseases in all systems of the body.

How are Americans doing when it comes to smoking? According to the 2005 National Health Interview Survey conducted by the National Center for Health Statistics, it is estimated that 24 percent of U.S. men, or 25.9 million, and 18 percent of U.S. women, or 20.7 million, currently smoke.

Even more troubling is that the smoking rates are highest among those living below the poverty level, at nearly 30 percent.

What about Cayuga County, how do we fare when it comes to smoking? Most recent statistics show that Cayuga County has the highest rate of adult smokers in all of the central New York counties. What's worse is that this rate has actually increased, from 25 percent of all adults in 2004 to 29.2 percent of adults in 2006. This is compared to the 2006 New York state average smoking rate of 20.5 percent.

If smoking is so prevalent and legal, why is it so concerning? When a cigarette is lit and inhaled, the smoke is taken into the upper respiratory track and the contents of the smoke are taken into the body. Although cigarette contents vary, cigarette smoke contains an estimated 4,600 chemicals. The most concerning of these are carcinogens, which can cause genetic mutations and are associated with cancer.

In addition, smoke contains various amounts of: nicotine, tar, asbestos, ammonia, arsenic, acetone, benzene, butane, carbon dioxide, chloroform vinyl chloride, cyanide, formaldehyde, lead and methanol. There are also toxic pesticides that are sprayed on tobacco plants and ultimately wind up being consumed by smokers.

Smoking is associated with the most lethal diseases known to man. Based on observational data, the Surgeon General first alerted the American public to the risk of smoking causing lung cancer in July 1957. Since then, research has indisputably linked tobacco exposure to lung cancer. Smoking is associated with roughly 80 percent of all lung cancers. In addition to lung cancer, tobacco is associated with cancers of nearly every organ system, including: lips and mouth, upper airways, digestive tract, pancreas, liver, kidneys, bladder, reproductive organs and the blood-based cancers like leukemia.

The deleterious effects of tobacco are well established on the cardiovascular system. Tobacco intake is known to increase the rate of heart attacks, strokes, life threatening arrhythmias, peripheral vascular disease and life threatening dilation of blood vessels called aneurysms. The nicotine directly damages and scars the lining of every blood vessel in the body, which results in cardiovascular diseases. Long-term smoking also causes the destruction of normal lung tissue resulting in chronic obstructive pulmonary disease, including recurrent bronchitis and emphysema. It also reduces lung clearing function and increased rates of upper respiratory tract infections and certainly worsening asthma. This, in addition to, the seemingly less important side effects like a reduction in the sense of taste and smell, the staining and odor on one's hair and teeth, premature aging and wrinkles and earlier menopause and impotence.

The outlook for those in immediate daily contact with second hand smoke is just as grim. It seems that second hand smoke imparts a similar risk to that of smokers. According to the American Heart Association Scientific statement on smoking, it is now estimated that close to 40,000 people die from cardiovascular diseases caused by second hand smoke.

What about mothers who smoke during pregnancy? They are exposing their developing baby to increased risks of: miscarriage and spontaneous abortion, premature birth, abnormal placental development, small birth weight babies, still born infants and some birth defects.

Next week, I'll discuss quitting.

Dr. David M. Donaldson is an Auburn native and currently a cardiologist at Massachusetts General Hospital in Boston.