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The simple answer is just one cigarette. Nicotine is a very addictive drug. Simple advice is stop now.
Some people can smoke heavily and not get cancer. Others who never smoked a cigarette die of lung cancer from second hand smoke.
According to the CDC,
"Tobacco use remains the single largest preventable cause of death and disease in the United States. Cigarette smoking kills more than 480,000 Americans each year, with more than 41,000 of these deaths from exposure to secondhand smoke.1 In addition, smoking-related illness in the United States costs more than $300 billion a year, including nearly $170 billion in direct medical care for adults and $156 billion in lost productivity."
The National Cancer Institute stated,
"Smoking has been found to harm nearly every bodily organ and organ system in the body and diminishes a person’s overall health.
Smoking is a leading cause of cancer and death from cancer. It causes cancers of the lung, esophagus, larynx, mouth, throat, kidney, bladder, liver, pancreas, stomach, cervix, colon, and rectum, as well as acute myeloid leukemia.
Smoking causes heart disease, stroke, aortic aneurysm (a balloon-like bulge in an artery in the chest), chronic obstructive pulmonary disease (COPD) (chronic bronchitis and emphysema), diabetes, osteoporosis, rheumatoid arthritis, age-related macular degeneration, and cataracts, and worsens asthma symptoms in adults. Smokers are at higher risk of developing pneumonia, tuberculosis, and other airway infections (1-3). In addition, smoking causes inflammation and impairs immune function."
Please quit today,