On a quiet afternoon, I met Lao Li on a park bench. Lao Li is an interesting person, he is always optimistic and energetic even after retirement. Our conversation quickly turned to the topic of health, and Lao Li said to me with a smile: "You know, I have a pack of cigarettes a day, but I dare to say that my body, the doctor said it was good." This sentence made me smile, but it also made me think. Smoking has always been recognized as the enemy of health, why does Lao Li seem to have become the secret of longevity?
This reminds me of a popular misconception: "A pack of cigarettes a day is a race against a living immortal". Behind this view lies a misunderstanding of the complexity and multifaceted nature of the effects of smoking. As a doctor, I have witnessed the dangers of smoking to human health, especially the risk of lung cancer. However, a recent article in Nature reveals a perplexing phenomenon: why do some "smoking guns" seem to survive lung cancer?
Smoking has long been recognized as one of the leading risk factors for lung cancer, but the science behind it and why it affects different individuals varies greatly still needs to be understood**. The purpose of this section is to provide a straightforward and easy-to-understand scientific discussion on how smoking contributes to the development of lung cancer and to unravel the underlying causes of differences in response between individuals.
How does smoking cause lung cancer?
Direct effects of harmful chemicals:Tobacco smoke contains more than 7,000 chemicals, at least 70 of which have been identified as carcinogens. These chemicals, such as benzopyrene and nitrosamines, can directly damage the DNA of lung cells, causing them to mutate. Continuous DNA damage caused by long-term smoking is the direct cause of lung cancer.
The Role of Chronic Inflammation:Smoking can also trigger a chronic inflammatory response in the lungs. Long-term inflammation can lead to changes in the structure of lung tissues, increasing the chance of cell mutations and providing a "breeding ground" for the development of lung cancer.
Suppression of the immune system: Studies have shown that smoking suppresses the immune response in the lungs and weakens the body's ability to remove or repair damaged cells. This not only accelerates the accumulation of mutant cells, but also creates conditions for the growth and spread of tumors.
Genetic factors:There are significant differences in people's physiological responses to smoking, in part due to genetics. Some people's genetic mutations may reduce their risk of lung cancer by increasing their ability to repair DNA or altering their metabolic response to harmful chemicals.
Lifestyle & Environmental Factors:In addition to genetic factors, an individual's lifestyle and environmental exposures also play an important role in influencing lung cancer risk. For example, dietary habits, physical activity, occupational exposure, and air pollution may all affect the risk of lung cancer in smokers.
The significance of scientific research
Understanding how smoking causes lung cancer and why there are individual differences is critical to the development of targeted prevention and** strategies. By studying the interplay between smoking, genetics, and environmental factors, scientists are gradually demystifying the pathogenesis of lung cancer, providing more personalized prevention and ** options for high-risk groups.
Why some "smoking guns" don't get lung cancer.
Solve the mystery of "not getting lung cancer".
In exploring why some long-term smokers are spared from lung cancer, scientific research has revealed a number of factors. First, genetic makeup plays a key role in an individual's response to tobacco smoke. Specific genetic variants, such as those in lung cancer resistance-related genes (LCRGs), may provide some people with additional protection against lung damage caused by smoking.
In addition, individual lifestyle and environmental factors also play a role in this phenomenon. For example, people who eat a diet rich in antioxidants and vitamins may have a lower risk of lung cancer because these nutrients help protect against damage from harmful substances in smoke. Similarly, smokers who have regular lung health check-ups, through early intervention, may have a reduced risk of developing lung cancer.
Studies have further shown that certain components of tobacco smoke may affect cell proliferation and death by activating specific signaling pathways in the body. In some "bongs", these pathways may exhibit different activity due to genetic factors or lifestyle influences, thus affecting the likelihood of lung cancer development.
Beyond the dangers of lung cancer
Although some smokers may not develop lung cancer, smoking undoubtedly poses other serious health problems. Cardiovascular disease is one of the common health threats to smokers, including heart disease, stroke, and high blood pressure. The chemicals in tobacco smoke can damage the cardiovascular system, leading to hardening of the arteries and increased blood pressure, which increases the risk of cardiovascular disease.
Chronic obstructive pulmonary disease (COPD) is also a significant risk for smokers. This cluster includes chronic bronchitis and emphysema, which is characterized by dyspnea, persistent cough, and increased sputum. Lung inflammation and damage caused by long-term smoking is the main cause of COPD.
In addition, smoking has also been linked to many types of cancer, such as oral cancer, laryngeal cancer, esophageal cancer, pancreatic cancer, etc. The carcinogens in tobacco smoke can spread through the bloodstream to various parts of the body, increasing the risk of cancer in multiple organs.
Not only that, but smoking can also affect reproductive health, increase the risk of infertility, and also pose a threat to the health of the fetus. Smoking in pregnant women increases the risk of preterm birth, low birth weight, and stunting.