Smoking raises the risk of complications of Crohn’s disease. Research shows that if you smoke, quitting can improve symptoms and your overall health.

Cigarette smoking is the strongest environmental risk factor for the development and progression of Crohn’s disease. There are more than 7,000 chemical components in tobacco smoke, and at least 250 of them are harmful to your health.

If you have Crohn’s disease, smoking is likely making it worse. It also puts you at risk for developing cancer, heart disease, and other chronic conditions. And having multiple chronic conditions can make treating Crohn’s disease more challenging.

It’s hard to say exactly how all those chemicals in cigarettes affect Crohn’s disease, but there are some theories.

It may be that cigarette smoking changes the gut microbiome, which affects the colon. And some substances in cigarette smoke may affect blood flow to the intestines. Cigarette smoke may change the immune system and have an inflammatory effect.

Research links smoking to:

  • worse and more frequent inflammatory relapses
  • higher likelihood of recurrence after surgery
  • poorer response to therapy

According to Crohn’s & Colitis UK, smoking with Crohn’s disease is also linked to:

  • needing more steroids, immunosuppressants, and anti-TNF medications
  • narrowing of the bowel (strictures), which can lead to blockage
  • perianal disease (Crohn’s around the anus)
  • bone weakness and joint problems
  • higher risk of developing bowel cancer

E-cigarettes, also called vapes, are battery-operated devices that people use to inhale an aerosol containing nicotine, flavorings, and other chemicals.

There hasn’t been much research specific to e-cigarettes and Crohn’s disease. So, it’s not clear exactly how e-cigarettes affect people with this condition.

Most e-cigarette liquids contain nicotine, which affects the immune system and can promote inflammation. Research from 2020 suggests that some smokeless tobacco products raise blood nicotine levels even higher than cigarette smoking.

When you vape, you’re not inhaling smoke. But you’re inhaling aerosol into your lungs. That aerosol generally has fewer chemicals than cigarette smoke, but it still contains a lot of chemicals, including heavy metals, that are quite harmful to your overall health.

Smoke from cannabis, also called weed, may contain some of the same harmful chemicals as tobacco smoke.

Cannabis might offer some relief from Crohn’s symptoms, such as pain and diarrhea. But it might just be masking inflammation. A 2014 study found that people with Crohn’s disease who smoked cannabis for more than 6 months at a time were more likely to require surgery.

A systematic review from 2018 found some pros and cons to cannabis use with Crohn’s disease. Study authors drew no firm conclusions as to its safety and effectiveness but stated there’s no evidence that it helps maintain remission.

If you smoke, quitting can help you manage Crohn’s disease.

People with Crohn’s disease who smoke tend to have more aggressive disease, more complications, and a higher rate of surgeries than nonsmokers. A long-term study concluded that quitting smoking lowers the risk of complications and the need for surgery in people with Crohn’s disease.

An older review from 2005 found that people with Crohn’s who smoked more than 15 cigarettes per day had significantly more recurrences than lighter smokers.

Another study suggests that smoking is the most modifiable risk factor for Crohn’s disease progression. The researchers found that fewer people who stopped smoking at diagnosis had developed complications compared with those who continued to smoke.

The study also noted that smoking as few as three cigarettes a day substantially increased the risk of complicated disease. Notably, the researchers concluded that all people with Crohn’s disease who smoke can benefit from stopping, no matter when they were diagnosed or how many surgeries they’ve had.

Nicotine is highly addictive, which can make quitting smoking very challenging. No method works for everyone, and it’s common to slip back into old habits. The key is to let these setbacks go and start again. Here are some tips to get you on your way.

  • Call 800-QUIT-NOW (800-784-8669) to speak to a trained quit coach who can help you make a personalized plan. They can also let you know about services in your area. It’s free and confidential.
  • Check out resources such as,, and the American Lung Association.
  • Download a quit smoking app to track your progress and get support.
  • Identify your smoking triggers so you can avoid them or find alternatives.
  • Once you have a plan in place, choose a day to quit.
  • Consider nicotine replacement therapy. You can buy gum, patches, and lozenges without a prescription and nasal spray and inhalers with a prescription. These products help you gradually reduce the amount of nicotine you get until you’re ready to stop altogether.
  • Ask your doctor about bupropion (Aplenzin, Forfivo, Wellbutrin) and varenicline (Chantix). These prescription medications can help dampen your craving to smoke.
  • Try exercise to deal with stress and reduce cravings.
  • When the urge to smoke hits, try candy, sugar-free gum, or deep breathing exercises until it passes.
  • Lean on friends and family for support.

There’s plenty of evidence that smoking can make symptoms of Crohn’s disease worse. It’s also clear that people with Crohn’s disease who smoke are more likely to experience complications. That may mean you’ll also need more medications and more surgery. And smoking increases the risk of developing other chronic diseases.

Vaping and smoking cannabis can also harm your health, but more research is needed to learn how they affect Crohn’s disease specifically.

If you smoke, quitting can help improve Crohn’s disease symptoms and lower your risk of developing complications. Working with a doctor and a quit counselor can help you formulate a plan of action you can stick with.