Smoking and Diabetes

Smoking increases your risk of getting Type 2 diabetes.

The more you smoke, the more chance you have of getting diabetes (DYE-uh-BEE-teez). If you smoke 16 to 25 cigarettes a day, your risk for Type 2 diabetes is 3 times greater than a non-smoker’s risk. When you quit smoking, your risk decreases during the years that follow.

Smoking affects the way insulin works in your body.

In Type 2 diabetes, the body does not respond to the insulin (IN-suh-lin) made by the pancreas (PAN-kree-us). Insulin helps blood glucose, or glucose (GLOO-cose), enter the body’s cells for fuel. When you smoke, your body is less able to respond to insulin. When your body resists insulin, your glucose levels increase. Resistance does not start to reverse until you do not smoke for 10 to 12 hours.

Smoking makes it harder to control your diabetes.

Studies show that smokers have poorer glucose control than non-smokers do. Ex-smokers have the same blood glucose control as non-smokers. When you have Type 1 or Type 2 diabetes, glucose control is very important.

The A1c (read “A-one-C”) test checks how well you control your glucose level over 3 months. The goal is to keep your A1c at 7 percent or less. When you have diabetes and you smoke, your A1c level increases. If you quit smoking, your A1c level may decrease to the same level as a non-smoker’s.

Smoking increases your risk for getting other problems from diabetes.

When you have diabetes and smoke, your chances are greater for getting other health problems from diabetes. These other health problems are called complications (COM-pli-KAY-shuns). You can get serious eye problems, kidney problems, and nerve problems. You can get heart and blood vessel disease, such as heart attack, stroke, and hardening of the arteries, especially in the legs.

Even for people who do not have diabetes but smoke, the risk of getting other health problems is greater. The more and the longer you smoke, the more your risk increases. Smoking and diabetes together greatly increase the danger of getting complications. To lower your risk, you must control your glucose levels and quit smoking

You benefit in important ways when you have diabetes and quit smoking.

When you quit smoking, you have:

  • Less resistance to insulin
  • Less chance of eye damage
  • Less chance of kidney damage and kidney failure
  • Less chance of nerve damage

Results of your blood tests may improve when you quit smoking.

Possible effects on your blood test results are:

  • Lower A1c levels
  • Lower glucose levels
  • Lower cholesterol levels
  • Lower LDL (bad) cholesterol levels
  • Lower triglycerides (fats) levels
  • Higher HDL (good) cholesterol levels

You get other benefits when you quit smoking.

You benefit in many ways when you quit smoking. You may have:

  • A longer life
  • More energy

You will have:

  • Less chance of a heart attack or stroke
  • Less chance of lung cancer and other cancers
  • Less chance of chronic bronchitis and emphysema
  • Fewer colds and respiratory infections
  • Less shortness of breath and coughing
  • Better blood flow to arms and legs
  • Warmer hands, legs, and feet
  • Better healing of wounds
  • Better ability to smell and taste
  • Less risk of gum disease
  • Money you saved from not buying cigarettes
  • No odor of stale smoke about you
  • Better hygiene
  • Freedom from addiction

If you want help to stop smoking:

  • Classes may be available in your community.
      • Call 1-800-553-UPMC (8762) to find out more.
  • If you are an inpatient at a UPMC hospital:
      • Ask your nurse if the hospital has the UPMC patient education TV channel, which features a video about quitting smoking.
      • Ask to talk one-on-one with a smoking cessation counselor.
  • Go to UPMC’s Patient Education website. Under the Smoking category is Journey to a Smoke Free Life, a 42-page guide that can help you devise a successful strategy to quit smoking, as well as other materials about the dangers of smoking and other health topics. You can print out any or all of these materials.
  • Additional resources are available from the toll-free Pennsylvania Department of Health Quit Line. Call 1-877-724-1090.
                                                                                                                                  Reviewed July 2013

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