Smoking and Diabetes Don’t Mix: 9 Reasons to Quit Smoking Now

Smoking isn’t good for anyone’s health. But smoking and diabetes are a particularly bad combination. If you have diabetes, quitting smoking is one of the best things you can do for your overall health and for your diabetes management. Let’s take a look at how smoking can worsen both Type 1 and Type 2 diabetes, and what you can do to stop smoking. 

How does smoking affect people with diabetes?

If you have diabetes, smoking increases your risk of developing diabetes complications. It can also make it harder for your body to respond to insulin and your diabetes medication. Here are nine ways smoking affects your health.

1. Increases inflammation

Smoking increases inflammation in the body. Uncontrolled inflammation leads to damage in your cells and tissue. Over time, this will worsen diabetes as well as heart and kidney disease. Inflammation also increases your risk of developing some types of cancer and other health conditions. 

2. Raises blood sugar

Smoking increases your blood sugar. People with diabetes who smoke have a much harder time managing their blood sugar. They also have more trouble finding the right combination of medication to manage their blood sugar levels.

If you have diabetes, keeping your blood sugar in a normal range is the most important thing you can do to stay healthy. The longer your blood sugar remains high, the more likely you are to develop serious health complications from diabetes.

3. Increases insulin resistance

​​Insulin resistance is when your body doesn’t respond appropriately to insulin. Nicotine (and possibly other harmful chemicals in cigarettes) causes insulin resistance. People with diabetes already have trouble processing extra blood sugar. And insulin resistance makes it even more difficult to keep blood sugar within a healthy range.  

4. Raises blood pressure

Studies show that people who have diabetes and smoke have a much higher risk of blood vessel damage. Blood vessels stiffen when they’re damaged, which can lead to high blood pressure. 

High blood pressure and diabetes increase your risk of heart disease, kidney disease, eye disease, erectile dysfunction, and stroke.

5. Leads to heart disease

Smoking leads to or worsens many conditions that increase the risk of heart disease. These include high blood pressure, diabetes, and high cholesterol. Heart disease can take many forms, like heart failure and coronary artery disease, which causes heart attacks and angina. 

EXPERT PICKS: WHAT TO READ NEXT

• Does nicotine raise blood sugar? Understand how smoking and vaping can affect people with diabetes.

• It’s never too late to quit. If you’re trying to quit smoking, it helps to know the many benefits you’ll experience once you stop.

• Want to quit “cold turkey”? Here are tips to help you through quitting cigarettes for good.

6. Damages kidneys 

You already know that smoking increases your blood sugar and damages your blood vessels. But did you know that over time these two things can also lead to kidney damage? 

Your kidneys depend on thousands of blood vessels in order to work. When blood vessels get damaged, your kidneys can’t do their job. This puts you at risk for diabetic kidney disease, a type of chronic kidney disease. 

7. Worsens vision

You might already be familiar with eye conditions related to diabetes, like diabetic retinopathy, cataracts, and glaucoma. Smoking also increases the risk of these conditions, as well as age-related macular degeneration. So the combined effects of smoking and diabetes are negative for your eye health, to say the least. And some of these eye conditions don’t have a cure, which puts you at risk for permanent vision changes and even blindness.

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8. Leads to poor circulation 

The two biggest contributors to peripheral artery disease (PAD) are Type 2 diabetes and smoking. PAD makes it harder for blood to flow through arteries in your limbs. This is similar to how damaged blood vessels result in kidney disease and high blood pressure. Poor circulation to your legs and feet increases the risk of infections, ulcers, and amputations. 

9. Causes nerve damage

High blood sugar and inflammation don’t just damage blood vessels. Your nerves are a target, too. This nerve damage can lead to pain, numbness, and tingling in your hands, legs, and feet. 

Diabetic neuropathy can be painful and make it hard to complete your daily activities. The blood vessel damage from smoking can also make neuropathy worse.

Can quitting smoking help manage diabetes?

Over time, yes — quitting smoking can help with diabetes. Studies show that A1C levels eventually come down over time, although they may increase a little in the year or so after quitting.

What’s more, quitting smoking will help you avoid the complications mentioned above. Many studies have shown that people with diabetes have a lower risk of heart disease, kidney disease, and related events in the years after quitting.

Timeline of improvements after quitting smoking

Everyone is different, so the response to quitting smoking will vary from person to person. But here’s a rough estimate of what you might expect:

• When you stop smoking, inflammation in your body will start to go down right away. 

• In a few months, your blood sugar and response to insulin will get better. You can also have improved circulation and lung function.

• After 1 year, your risk of heart disease can decrease by as much as 50%.

How can people with diabetes quit smoking?

Quitting smoking isn’t easy. But there are many tools available to help you:

• Smoking cessation programs help people quit smoking through support groups, education, and counseling.

• There are also prescription medications that can help you quit.

• Nicotine replacement therapy can help you manage nicotine withdrawal while quitting. But these products can affect your blood sugar level, so be sure to monitor.

• Quitting cold turkey is an option for anyone, but it helps to start with a plan.

Consider asking someone on your healthcare team to help you decide which might be best for you.

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Written by:

Tracy Norfleet, MD, FACP

Dr. Tracy Norfleet is a board-certified Internal Medicine physician, health expert, and physician leader with over 20 years of experience practicing adult medicine. Dual-certified by the American Board of Obesity Medicine and the American Board of Lifestyle Medicine, Dr. Tracy possesses a wealth of knowledge and expertise in both traditional medical practices and innovative lifestyle interventions for chronic disease management and reversal.

Edited by:

Sophie Vergnaud, MD

Sophie Vergnaud, MD, is the Senior Medical Director for GoodRx Health. A pulmonologist and hospitalist, she practiced and taught clinical medicine at hospitals in London for a decade before entering a career in health education and technology.

Reviewed by:

Mandy Armitage, MD

Mandy Armitage, MD, has combined clinical medicine with her passion for education and content development for many years. She served as medical director for the health technology companies HealthLoop (now Get Well) and Doximity.

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