The Truth About UC and Smoking

by Emily Shiffer Health Writer

If you have ulcerative colitis (UC), you might have heard through the grapevine that smoking cigarettes may improve—or even prevent—symptoms of this inflammatory bowel disease (IBD). While it does sound bananas, there is some research to suggest it could be true. But before you even think about picking up a cigarette, know that other research suggests the opposite. And that’s not even counting the gazillion other proven dangers—increased risk for heart disease, stroke, various cancers—that come with smoking. Read on to learn what we know—and what still baffles us—about the UC-smoking connection.

Smoking May Subdue Symptoms

Ulcerative colitis is an autoimmune disease that causes inflammation and ulcers in the colon, leading to abdominal pain and diarrhea mixed with blood. So how does smoking make UC symptoms less severe? According to David Magier, M.D., a gastroenterologist at NYU Langone Health in New York City, “Nicotine or smoking byproducts suppress the immune system, which is overactive in individuals with ulcerative colitis. Medications approved to treat these symptoms work in the same manner.”

Smokers Are Less Likely to Develop UC

Despite some conflicting research, smoking appears to protect people from developing UC, says Stephen Hanauer, M.D., professor of medicine-gastroenterology and hepatology at Northwestern Medicine in Chicago, Ill. The numbers bear this out: Both nonsmokers and former smokers have higher rates of the disease. What’s more, quitting smoking can lead to the development of UC down the line. “While most patients develop ulcerative colitis as teenagers or young adults, ex-smokers account for a smaller, second-age peak of ulcerative colitis in the fifth or sixth decade of life,” Dr. Hanauer adds.

Women Smokers With UC See Fewer Benefits

While some studies show that smoking is protective against UC, research published in Clinical Gastroenterology and Hepatology suggests a gender divide. In one study, smokers of both sexes were compared with non-smokers. The age of UC onset was delayed in male smokers, with no symptoms appearing until age 41, versus male non-smokers, who experienced symptoms by age 32. This age discrepancy was not seen among women smokers versus non-smokers. The typical age of UC onset in women was 33 in both groups. While smokers of both sexes had less severe disease than nonsmokers, the benefits were more marked for men.

doctor using stethoscope to examine patient

The Apparent UC Benefits From Smoking Don't Outweigh the Risks

Despite these findings, you should not start smoking if you have UC, says James Lindsay, Ph.D., a gastroenterologist and professor of inflammatory bowel disease (IBD) at the London School of Medicine. “There is clear evidence that smoking cigarettes reduces disease severity in those with UC,” he agrees, but the negative effects from smoking far outweigh any health benefits, he adds. “Smoking increases risk of heart disease and stroke. We advise all our patients to stop smoking.” If you’re a smoker with UC, always discuss quitting with your doctor first. (More on this in a moment.)

researcher looking at stats

New Research Challenges Older Findings

Recent research hasn't backed up earlier findings. Case in point: A 2019 study published in the journal Alimentary Pharmacology and Therapeutics found that smoking provides no discernible benefits for anyone with UC, male or female. When smokers and nonsmokers with UC were compared, they shared a similar risk of disease flares, need for immune-suppressing medications, hospitalization, and colectomy (when the affected part of the colon is removed through surgery). And yes, the study’s authors warn people with UC not to smoke.

Group of doctors at work in hospital operation theater

Former Smokers Have More Severe UC Symptoms

Researchers still don’t understand why, but former smokers with UC are more likely to require more intensive therapy with corticosteroids, immune suppressants, and biologic therapies than current or never-smokers, says Dr. Hanauer. “Ex-smokers are also more likely to require surgery to treat ulcerative colitis than non-smokers, and they’re more likely to develop chronic inflammation of a surgical J-pouch [chronic pouchitis] than non-smokers.” We know, this may seem like incentive not to quit. But even with these additional risks, the dangers of smoking to your overall health are much more severe.

Smoking Ups the Odds of Getting DVTs and Blood Clots

“Patients with ulcerative colitis have a higher risk of deep venous thrombosis,” or DVT, a blood clot that develops in one of the major veins of the lower legs, thighs, pelvis, or arms, says Jessica Philpott, M.D., Ph.D., a gastroenterologist at the Cleveland Clinic in Ohio. Smoking may increase the risk for other blood clots, too, although studies have not yet determined if this risk is additive for people with UC. No need to wait for hard answers though: Blood clots in the legs can cause pain and swelling and may lead to pulmonary embolism, a life-threatening blood clot in the lungs.

Smoking Increases Bone Loss

Another reason to quit cigarettes: Some 30% to 60% of patients with UC have lower-than-average bone density, likely due to ongoing corticosteroid therapy, according to the Crohn's and Colitis Foundation. Dr. Philpott notes that smoking—along with family history of fracture, being a woman, and advanced age— can increase the risk. To prevent bone loss, talk to your doctor about reducing your steroid use, eat a diet rich in calcium, and consider taking a vitamin D supplement.

woman's hand putting on nicotine patch

Nicotine Might Be a Potential Treatment for UC—Someday

Researchers are studying whether nicotine-replacement therapies—including gum, patches, and nicotine enemas—can relieve UC symptoms in the same way smoking does. Although some people with UC report finding symptom relief from patches and gum, the science proving a benefit still isn’t there. And right now, nicotine is not a recommended therapy for UC, Dr. Magier adds. He prescribes 5-aminosalicylic acid treatments (rectal or oral), steroids, and anti-TNF injections instead.

man talking to doctor

Always Create a Quit Plan With Your Doctor

Ready to quit? Good for you! But see your UC specialist first. People with UC who quit smoking may experience a flare a few weeks or even months later, according to Dr. Magier. This may be because of the immune-suppressing effect of nicotine has been lost. “If the symptoms are severe, such as extreme weight loss or bleeding, the individual may even require hospitalization,” he adds. We know this could be an excuse not to kick your habit. But by working with your doctor, you have a better chance of avoiding short-term complications and reaping the benefits of a cigarette-free life.

Emily Shiffer
Meet Our Writer
Emily Shiffer

Emily Shiffer is a former digital web producer for Men’s Health and Prevention, and is currently a freelancer writer specializing in health, wellness, weight loss, and fitness. She is currently based in Pennsylvania and loves all things antiques, cilantro, and American history.