Major cause of lung cancer
Written by Mystic on Tuesday, August 05, 2008Tobacco smoking is the major cause of lung cancer. Over 75% and possibly as much as 90% of all lung cancer can be attributed to smoking.
Lung cancer is most common in adults aged between 40 and 70 years who have smoked for around 20 years. If the smoking commenced in teenage years, the risk of developing lung cancers is 2-3 times greater.
Cigarette smoke contains many cancer causing substances including benzene, arsenic and cadmium. Some components of the cigarette react chemically with the DNA within the body cells and damages a gene known as the p53 gene. This gene is responsible for correcting errors within the cells. If the gene is damaged the cell loses this protective mechanism and this leads to an increased susceptibility to cancer.
Passive smoking or environmental tobacco smoke not only brings about respiratory problems in adults, children and infants but has also been shown to contribute to lung cancer in non-smokers.