Foreign Related Studies on Smoking

Impact of Cigarettes and Alcohol on Colorectal Cancer Risk http://coloncancer.about.com/od/smoking/a/Smoking_Cancer.htm Researchers examined data from 845 people with colorectal cancer to determine if smoking and drinking may have influenced their chances of developing the disease. Their findings, published in the journal Epidemiology, were pretty straightforward. Consuming more than seven alcoholic drinks a week increased the risk of colorectal cancer by 72 percent. Smokers were more likely to develop rectal cancer, with risk increasing as the number of cigarettes increased (from 43 percent higher risk for light smokers to 164 percent higher risk for heavy smokers).

No Such Thing as a Safe Cigarette... Smokerhttp://coloncancer.about.com/od/smoking/a/SecondhandSmoke.htm

Another study, another thorn in the side of smokers. People who choose to smoke already know it's bad for them, but a report released by the U.S. Surgeon General reminds smokers just how bad it is for everyone around them, too. According to the report, entitled "The Health Consequences of Involuntary Exposure to Tobacco Smoke," even brief exposure to secondhand smoke can cause immediate harm to people's health. The report states unequivocally that secondhand smoke causes premature death and disease in children, as well as in adults who don't smoke.

Smoking Increases Risk for Carriers of HNPCC Gene http://coloncancer.about.com/od/cancerresearch/a/12152004.htm A study published in the Archives of Internal Medicine analyzed carriers of two HNPCC mutations to determine what lifestyle factors might increase their risk of developing colorectal cancer.

People who carry the gene mutation(s) linked to hereditary non-polyposis colorectal cancer (HNPCC) are extremely likely to develop colorectal cancer at some point in their lives. In this study, researchers examined how alcohol and tobacco influenced the risk of developing colorectal cancer in carriers of the hMLH1 or hMLH2 mutation, both of which are known to lead to HNPCC.

The study found that alcohol use didn't seem to have much of an impact but tobacco use did. Specifically, men who carried the hMLH1 mutation and used tobacco developed HNPCC earlier than men who carried the hMLH1 mutation and didn't use tobacco.

Smoking Causes Genetic Damage Linked to Colon Cancer http://coloncancer.about.com/od/cancerresearch/a/11202000.htm A report published in the Journal of the National Cancer Institute found that smoking cigarettes may cause colon cancer by damaging genes. Researchers examined tissue samples from more than 1,500 colon cancer patients and compared them to tissue samples from about 2,400 people without colon cancer. They found that the smokers had twice the risk of developing colon tumors with microsatellite instability (MSI). MSI inhibits cells' ability to repair damaged DNA and therefore promotes cancer development. According to the study, inherited genetic flaws account for 2-5% of colon tumors with MSI. However, MSI shows up in about 10-15% of all colon tumors. This study suggests that genetic damage caused by smoking probably helps explain the difference.

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Impact of Cigarettes and Alcohol on Colorectal Cancer Risk http://coloncancer.about.com/od/smoking/a/Smoking_Cancer.htm No Such Thing as a Safe Cigarette... Smokerhttp://coloncancer.about.com/od/smoking/a/SecondhandSmoke.htm Smoking Increases Risk for Carriers of HNPCC Gene http://coloncancer.about.com/od/cancerresearch/a/12152004.htm Smoking Causes Genetic Damage Linked to Colon Cancer http://coloncancer.about.com/od/cancerresearch/a/11202000.htm