Smoking Is Worse Than We Thought
New research documents increased risks from cigarette smoking has gone from bad to worse.
For millions of Americans, cigarette smoking seems to temporarily serve as a stress reliever and social outlet. A recent comprehensive study, however, has revealed that tobacco smoke triggers a larger variety of cancers and is a much deadlier carcinogen than researchers had previously realized. The study was chaired by Jonathan Samet, MD, of the Johns Hopkins School of Public Health, Baltimore, and provides the first definitive evidence that secondhand smoke causes lung cancer, which increases the risk to those people exposed by about 20%. There are 4,000 chemicals in cigarette smoke and other recent studies have shown that they can be measured in nonsmokers body fluids and urine.
Samets study firmly links smoking to stomach, liver, cervical, and kidney cancer, which in the past was suspected, but not proved. The team of investigators researched more than 3,000 studies involving millions of smokers. When all the information was compiled, it was found that at least half of the estimated 1.2 billion smokers in the world will die prematurely of smoking-related illnesses, including cancer, heart disease, and emphysema.
Previous studies indicated that smokers had three to four times the normal risk for tumors of the bladder and kidney, but the new study revealed that it was in fact five to six times. Another interesting outcome of the study revealed that smoking doubles the risk of certain cancers that are associated with other factors. Some examples include cervical cancer and human papillomavirus, stomach cancer with the bacterium Helicobacter pylori, and liver cancer with the hepatitis virus. For more information, visit www.iarc.fr.