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Why should I quit smoking?

The Effects of Smoking

  • Smoking may result in as many as 400,000 deaths in the United States each year.
  • Smoking is a major risk factor for heart disease. It contributes to about one quarter of all heart disease-related deaths in the U.S.
  • Smoking increases your risk for a heart attack by two to six times. Your risk increases with the number of cigarettes you smoke.
  • If you're a smoker and you have a heart attack, you're more likely than a nonsmoker to die from the heart attack or to die suddenly.

Smoking Hurts Your Heart

Smoking harms your heart and blood vessels in several ways:

  • It raises your blood pressure. Each time you smoke, your blood pressure rises for a short time. This does not cause chronic high blood pressure. However, if you already have high blood pressure, smoking may aggravate your condition. By quitting smoking, you can avoid the short-term changes in your blood pressure that occur when you smoke.
  • It changes your blood fats, decreasing HDL cholesterol, which is known as the good cholesterol. For instance, shortly after quitting, your HDL level may rise as much as 6 to 8 mg/dL. Within one year, your HDL level may return to the healthier level of a nonsmoker.
  • It damages the lining of your blood vessels, making them more prone to plaque buildup. It speeds the buildup of plaque in the arteries that supply blood to your heart, called the coronary arteries.
  • It makes plaque in your coronary arteries less stable. This means the plaque is more likely to crack, which can lead to a heart attack.
  • It reduces oxygen to your heart. The carbon monoxide in the smoke decreases your blood's capacity to carry oxygen. So when you smoke, your heart - and the rest of your body - has less oxygen available to it.
  • It may trigger an abnormal heart rhythm. Smoking affects the part of your nervous system that controls your heart rate. It can interfere with the electrical activity in your heart and cause heart rhythm problems called arrhythmias. Arrhythmias may occasionally be serious, and some are life threatening.

Even if you've smoked for a long time, quitting will decrease your chances of developing heart disease. In fact, within several years after quitting, your risk of a heart attack may be reduced almost to the level of a nonsmoker.

Smoking Increases Your Risk for Many Health Problems

Smoking increases your risk for other conditions, too, including these:

  • lung cancer
  • mouth cancer
  • cancer of the vocal cords
  • cancer of the esophagus
  • cancer of the urinary tract
  • kidney cancer
  • cancer of the pancreas
  • cervical cancer
  • chronic lung disease, including bronchitis and emphysema
  • stroke
  • pregnancy complications, including miscarriage, stillbirth, and premature delivery. Also, babies of mothers who smoked during pregnancy are more likely to have sudden infant death syndrome.

For more common questions and expert answers on quitting smoking, visit