The nicotine present in smoke causes heart disease by:
* Decreasing oxygen to the heart.
* Increasing blood pressure and heart rate.
* Increasing blood clotting.
* Damaging to cells that line coronary arteries and other blood vessels.
A person's risk of heart disease and heart attack greatly increases with the number of cigarettes he or she smokes. People who smoke have a two to four time higher chance of having heart disease. And smokers continue to increase their risk of heart attack the longer they smoke. Women who smoke and also take birth control pills increase several times their risk of heart attack, stroke, and peripheral vascular disease.
Smoking is a leading cause of stroke. Smoking can make blood thicker and more likely to clot, increase the buildup of plaque in blood vessels leading to the brain, pain in the hands and feet; may be severe and damage blood vessels in the brain.
Benzene is a known cause of acute myeloid leukemia, and cigarette smoke is a major source of benzene exposure. Cigarette smoking increases the risk of developing mouth cancers. This risk also increases among people who smoke pipes and cigars. For smoking-attributable cancers, the risk generally increases with the number of cigarettes smoked and the number of years of smoking, and generally decreases after quitting completely. The combination of smoking and alcohol consumption causes most laryngeal cancer cases. Cancer-causing agents in tobacco smoke damage important genes that control the growth of cells, causing them to grow abnormally or to reproduce too rapidly.
Smoking causes more than four in five cases of lung cancer. Lung cancer has one of the lowest survival rates of all cancers, and is the most common cause of cancer death. The good news is that most of these deaths are preventable, by giving up smoking in time.
Smoking is a leading cause of heart disease. Smoking can:
• Raise triglycerides i.e. a type of fat in your blood
• Lower "good" cholesterol (HDL)
• Damage cells that line the blood vessels
• Cause thickening and narrowing of blood vessels
• Cause clots to form, blocking blood flow to the heart
Smoking also increases the risk of over a dozen other cancers including cancers of the mouth, larynx , pharynx , nose and sinuses, esophagus , liver, pancreas, stomach, kidney, bladder, cervix and bowel, as well as one type of ovarian cancer and some types of leukemia. There is also some evidence that smoking could increase the risk of breast cancer.