Smoking and Increased Risk for Diabetes

Most people are aware that smoking cigarettes increases their risk of lung diseases—like cancer or chronic obstructive pulmonary disease (COPD)—but smoking also affects people with diabetes and can increase the complications of that health condition.

A 2014 Surgeon General’s report revealed that people who smoke cigarettes are at a 30%–40% higher risk for developing type 2 diabetes than nonsmokers. Even among people who smoke cigarettes, the report found different risk levels and that the more cigarettes smoked, the higher the risk for developing diabetes.

Can Smoking Cause Diabetes?

Smoking does contribute to the risk of developing type 2 diabetes. This is attributed to the increased inflammation and oxidative stress smoking causes, a result of harmful chemicals from cigarettes combining with oxygen in the body to damage cells.

High levels of nicotine in the body can decrease the effectiveness of insulin and make it harder for smokers to control their blood sugar levels.  

Other risk factors for developing diabetes include:

• Age
• Ethnicity
• Being overweight, especially in those carrying extra weight in the abdomen
• Family history

Other Health Complications

Both diabetes and smoking can damage cells and tissues due to the increased inflammation and increased strain diabetes and smoking both place on blood vessels.

Some health complications that people with diabetes who also smoke are at an increased risk for include the following.

Cardiovascular Complications

The health of the heart and blood vessels is affected by both diabetes and smoking.

• Smoking is known to cause damage to blood vessels by increasing inflammation. It also increases the risk of forming plaque in blood vessels, which can either completely occlude blood vessels or cause a heart attack or stroke.
• Uncontrolled diabetes can damage blood vessels, especially smaller veins and arteries, by producing elevated amounts of sugar in the blood.

Circulation Problems Leading to Lower Extremity Infections, Ulcers, and Amputations

The strain that both smoking and diabetes places on blood vessels increases the risk for slow wound healing and ulcers that affect the arms and legs and especially the feet.

Decreased blood flow resulting from smoking and diabetes interferes with wound healing. In some cases, the infections in people's limbs can become so severe that amputations are required.

Kidney Disease

The kidneys are another organ commonly damaged by both diabetes and smoking. Chronic kidney disease affects the kidneys' ability to filter wastes, toxins, and excess nutrients from the body. The buildup of these substances can lead to serious health complications, including kidney failure.

In the final stage of renal disease, people often require dialysis to remove the buildup of wastes, or even a kidney transplant.

Retinopathy

Retinopathy is a complication of diabetes that affects the eyes and can lead to impaired vision and, in some cases, blindness. Retinopathy isn't reversible, but early intervention to control blood sugar levels can stop the progression of the disease.

Early symptoms of retinopathy include:

• Dark areas of vision
• Blurry vision
• Floaters
• Challenges perceiving colors

Peripheral Neuropathy

Diabetes is a common cause of peripheral neuropathy, which is damage to nerves outside of the brain and spinal cord (the peripheral nerves), typically affecting the hands and feet. Symptoms of peripheral neuropathy are:

• Weakness
• Numbness
• Pain from nerve damage

Smoking has been identified as a risk factor for diabetic peripheral neuropathy, sensory nerve damage caused by high blood sugar levels and diabetes. The increased inflammation and oxidative stress caused by cigarette smoking is likely the reason it impacts the health of the nerves in the legs, feet, and hands.

Reducing Risk

Treating diabetes and quitting smoking are both important to improving your overall health and in lowering the risk of developing the health complications associated with diabetes and smoking.

When it comes to managing diabetes, monitoring blood sugar levels is crucial.

The A1C test (also called a glycated hemoglobin test) is used to measure your average glucose levels over the past three months by determining what percentage of hemoglobin proteins in your blood are coated with sugar, or glycated. Because new red blood cells are produced every three months, an A1C test can help determine how well you are controlling blood sugar levels over this period of time.

Monitoring blood sugar levels is one way of managing diabetes. Incorporating lifestyle changes and using medications if they are recommended by your healthcare provider are other ways.

Improvements to your lifestyle can have a big impact on your blood sugar levels, and it may even be possible to manage diabetes through lifestyle changes alone, without needing medications.

Smoking Cessation

Research shows that stopping smoking can reduce the risk of developing the complications caused by cigarettes. Even though the risk of diabetes in people who smoke may still be higher than for those who have never smoked, that risk decreases each year after you stop smoking.

It's important for everyone to stop smoking for their health, but it is especially important for people who have diabetes. This is because high nicotine levels in the body change the effectiveness of insulin and increase the risk of developing complications.

Weight Loss

Research shows an average weight loss of 10% in people who are overweight improves the body's response to insulin. One of the reasons being overweight—particularly when carrying weight in the midsection—contributes to the risk for diabetes is because it decreases the body’s ability to utilize insulin.

Losing weight can make the insulin produced by the body more effective, even reducing the need for medications to manage diabetes.

Dietary Changes

Changes to diet are important with diabetes. Diets high in carbohydrates raise blood sugar levels because the body breaks down carbs into glucose. Dietary changes also are necessary to help you lose weight and to maintain that weight loss.

Working with a dietitian, a healthcare provider, or a certified diabetes educator can help you make effective and sustainable changes that are personalized to your dietary needs.

As a rule of thumb, incorporating more vegetables, fruits, whole grains, and lean proteins is a great start to a healthy diet.

Increase Physical Activity

Physical activity increases the body's ability to use insulin effectively by lowering blood sugar levels and boosting energy. A few ways to increase physical activity throughout the day is by going for a walk, working out on your own, or attending group fitness classes.

Smoking Cessation Resources

Because nicotine is addictive, it can be very difficult to quit smoking. Fortunately there are tools that can help.

Tips to quit smoking include:

• Try nicotine replacements, such as patches, gums, or medications
• Avoid situations and locations associated with smoking
• Distract yourself from the cravings by chewing sugar-free gum, something crunchy like celery, going for a walk, or participating in a hobby like needlework that gives the hands something to do
• Practice stress management techniques, such as meditation, journaling, yoga, or deep breathing
• Join an online or in-person smoking-cessation group for social support while quitting and to hear of other people’s efforts in managing tobacco cravings

A Word From Verywell

Smoking cessation is important for everyone in general, but it is especially important for people who have chronic diseases like diabetes. Quitting smoking and managing your blood sugar levels can decrease your risk of developing complications of diabetes.

Maintaining a relationship with your primary care healthcare provider or an endocrinologist is important in monitoring and controlling blood sugar levels. Lifestyle changes can help as well.