Women smoking a pack
or more a day the risk is more than 4 times as great as the other women. Inhaling
is a significant factor. Every smoker gets some smoke into his Lung, but
purposeful inhalation multiplies the amount. Men who think they do not inhale
or inhale only slightly have 8 times the risk and men who inhale deeply have 14
times the risk of lung cancer as against non-smokers. Women who do not inhale
or who inhale only slightly have it and women who inhale moderately or deeply
3.7 times the risk in comparison with those who do not smoke.
The earlier
smoking starts, the greater the risk. Men who begin before 10 years of age have
nearly 5 times as much risk as those who start after the women who start before
25 run twice the risk of women who start Liter. Although lung cancer sometimes
does occur in nonsmokers, this is so relatively rare that it is estimated by
authorities that at least 90 percent of lung cancer deaths would not occur if
there were no smoking of cigarettes. Other cancers are associated with smoking.
The incidence of cancer of the larynx is 6 times as great
and that of cancer of the esophagus 4 times as great in men cigarette smokers,
aged 45 to 64, as in nonsmokers. Similarly, cancer of the pancreas is 2.7 times
as great, cancer of the liver and biliary passages 2.8 times, cancer of the
urinary bladder 2 times, cancer of stomach and kidney 1.4 times, and leukemia
1.4 times as great.
Women smokers have death rates 1.8 times as high as
nonsmokers for cancer of the mouth, larynx, esophagus, and pancreas. Pipe and
cigar smokers have rates for lung cancer twice as high as nonsmokers; for
cancer of the oral cavity, 4.9 times as great; for cancer of esophagus and
larynx, 3 to 4 times as high. While the cancer death rates associated with
smoking are not as high in women as in men, it seems likely that they will
catch up because of the great increase of smoking by women in recent years.
