For cancer, risk factors are a long-term process, which is often the result of multiple factors. Therefore, most etiological studies use "probability" to explain the pathogenicity of a risk factor, not absolute.
Why do some people smoke all their lives without getting lung cancer? The medical community has gradually realized that lung cancer may be a disease caused by external factors through internal factors. Risk factors can induce malignant transformation of cells and irreversible genetic changes, which means that long-term smoking actually faces the situation of gene mutation leading to cancer, and the possibility will be higher and higher.
Some smokers will not get lung cancer, which is probably just a random event, which does not mean that smoking has no effect on lung cancer.
In fact, the relevant institutions also have a certain assessment of the carcinogenic risk of smoking. If you quit smoking at the age of 30, 40 or 50, the later you quit smoking, the higher the risk of accumulating cancer. Even so, some friends who smoke have never had lung cancer.
Genetic Causes Researchers at UCLA and other institutions published an article in the Journal of Geriatrics, saying that a recent study specifically studied the genomes of some people who smoked and lived long, and found that there were different genetic variations among these people. However, such people are rare.
There are 2 15 single nucleotides in the genome of people who smoke for a long life. These single nucleotide polymorphisms can make human cells more capable of repairing damage. Although these people smoke, the cells in their bodies are more resistant to the harm caused by smoking than ordinary people.
Although such people have better lung function, they are not enough to strike. In addition, these people may pay more attention to exercise and lung health, so even if smoke is harmful to the body, the harm is not particularly great for this person.
It is normal for some people never to smoke, but they have lung cancer. It is not that smoking is the only way to get lung cancer, but smoking will greatly increase the possibility of getting lung cancer. Other bad conditions or living habits will also affect lung function and cause lung cancer.
In fact, there is a "gray zone" between the people who are not sick and those who are sick. During this period, if we can pay attention to the details of life and adjust our lifestyle, we can reduce the probability of getting sick. Every growing body cannot be completely filled with all kinds of bad habits. Since smoking has seriously reduced points for the body, in order to stay healthy, we need to add points for the body through other aspects, such as good eating habits, reasonable exercise, regular work and rest time and so on.
Don't say that it is meaningless for old smokers to quit smoking. Many old smokers said that after smoking for so many years, they are still in good health, not as uncomfortable as others said, and there is no need to quit smoking when they are old. Others feel that their bodies are used to smoking, and they will get sick if they quit smoking.
In fact, smoking is very harmful to the health of old smokers. You can't think that smoking is harmless just because of your feelings. These injuries often require medical examinations such as lung function and chest CT to display intuitively.
Conclusion For many heavy smokers, if they still can't quit smoking in a short time, it's best to avoid some peak periods when smoking is harmful to health and try to control themselves to smoke less. Slowly, you will feel that smoking is actually not as harmful as you think.
With the growth of age, the disadvantages of smoking become more and more obvious, because all the functions of the body are declining, and the reduction is greater than the addition, and the body will have problems. Quitting smoking as soon as possible is a foolproof policy.