The reasons to quit smoking are legion. In terms of your cardiovas- cular health, quitting smoking is a major way you can take control
of your risk of coronary artery disease and other heart and blood vessel diseases. Brie?y, these are the ways in which tobacco smoke endangers your cardiovascular system:
• Atherosclerosis. Smoking damages the lining of the arteries that supply your heart, brain, and the rest of your body with blood. The roughened, damaged walls are more susceptible to the formation of plaque. As the plaque forms, it restricts the ?ow of blood, a process called atherosclerosis. If your coronary arteries are affected, it dra- matically increases your chances of a heart attack. If the arteries to your brain are blocked, you may have a stroke. Atherosclerosis is also a risk factor for developing peripheral artery disease, which affects the arteries to your arms and legs. In combination with other factors (high blood pressure, high cholesterol), it is even more dangerous (see page 71). Smoking even one cigarette a day can harm the endothelium, or inner lining of your blood vessels.
• Blood clots. Smoking causes your blood to clot more easily.
Smoking encourages the formation of blood clots by causing platelets to stick together, which is often part of the cascade of events leading to a heart attack and stroke. A blood clot can block an artery and lead to heart attack, stroke, or peripheral artery disease. Some scientists think the blood-clotting effect of smoking is even more important than its role in inducing atherosclerosis.
• High cholesterol. Tobacco smoke decreases HDL cholesterol, or good cholesterol.
• High blood pressure. Although smoking does not directly cause high blood pressure, it temporarily constricts the diameter of the blood vessels to your heart.
• Constriction of arteries. Apart from the blockages within arter- ies caused by atherosclerosis, smoking causes your arteries to con- strict, reducing blood ?ow.
• Less oxygen in your blood. The nicotine and carbon monoxide in smoke get into your blood and reduce the amount of oxygen it can carry. This effect causes your heart to beat faster in order to try to keep the oxygen supply adequate.
• Family health. A recent report by the Surgeon General con- ?rmed that secondhand smoke in any amount carries health risks to those who live with smokers. The report summarized major research on how secondhand smoke can cause cancer, respiratory problems, and cardiovascular disease. To maintain or improve the health of your partner, children, or other people you live with, stop smoking now.
These harmful effects all interact to harm your heart and blood vessels. In addition, of course, smoking damages your lungs and increases your risk of developing cancers of the lung, throat, stomach, and bladder, and several other cancers.