These Habits Were Most Linked To A Chronic Gut Condition, Per A Massive Review
You notice it gradually: the bloating that doesn't go away, the cramping that shows up without warning, the meals that leave you feeling worse than before. For people living with ulcerative colitis (UC), a chronic inflammatory condition of the colon, that's a daily reality. What's less clear is why some people develop it and others don't.
A new systematic review1 pooling data from 30 studies and more than 148,000 people looked at which everyday habits and exposures showed up most consistently in people who developed it.
What the review looked at
The goal of this systematic review and meta-analysis was to identify which diet, lifestyle, and environmental factors may influence a person's risk of developing UC, which is becoming more common worldwide.
To do that, researchers pooled data from 30 observational studies including 148,468 people with UC and examined 17 potential risk factors, from dietary habits and smoking to antibiotic use and early-life exposures.
Habits linked to higher UC risk
Several factors showed up more often in people who developed UC.
- Daily egg consumption: Eating eggs every day was linked to a higher risk, though the evidence here was low certainty.
- Family history of IBD: Having a close relative with inflammatory bowel disease was one of the stronger risk signals in the review, consistent with what we already know about the genetic side of the condition.
- High antibiotic exposure: This wasn't about taking antibiotics once or twice. The link was specific to the highest levels of cumulative use. Repeated courses of antibiotics can reshape your gut microbiome for years afterward, which may explain why people with the greatest exposure showed higher UC risk, and why it's worth using them only when medically necessary.
- Ever smoking and former smoking: Both were linked to higher UC risk. Current smoking showed a lower risk in case-control studies, but that pattern didn't hold in cohort studies, so the data is inconsistent and it's not a finding that points toward any protective strategy.
Habits linked to lower UC risk
Several factors showed up more often in people who didn't develop UC.
- Fruit intake: Eating fruit regularly was linked to lower UC risk, likely thanks to its fiber, antioxidants, and plant compounds that may support gut health.
- Coffee consumption: Coffee drinkers had a lower risk too. The leading theory points to polyphenols (natural plant compounds with anti-inflammatory properties), though researchers are still working out exactly how it reduces inflammation.
- Pet exposure: Growing up with pets was associated with lower risk, consistent with the idea that early exposure to a wider range of microbes may help the immune system develop in a way that's less prone to inflammation.
- Appendectomy: Having your appendix removed was linked to lower UC risk. Researchers think this may relate to the appendix's role in immune signaling in the gut.
- Intermediate educational attainment: This one is harder to interpret. The researchers note it likely reflects a mix of lifestyle, healthcare access, and socioeconomic factors rather than education itself.
- Light alcohol consumption: A modest protective association showed up here, though heavy drinking showed no benefit, and alcohol comes with its own health considerations.
Factors with no clear association
Several commonly discussed factors showed no meaningful link to UC risk in this review, including BMI, oral contraceptive use, tonsillectomy, previous gastrointestinal infection, place of residence, any antibiotic use (as opposed to the highest category specifically), tea consumption, and heavy alcohol consumption.
What this means for your gut health
All 30 studies were observational, meaning researchers tracked what people were exposed to and then looked at who got UC. These types of studies can show associations, but it can't prove cause and effect. Most of the evidence here was low to very low certainty, with only 4 of 22 associations hitting moderate certainty.
That said, a few patterns are consistent with other IBD research too.
Eating more fruit and drinking coffee (if it works for you) both showed protective associations. On the flip side, high antibiotic use showed a risk signal, so if you've recently finished a course, there are evidence-based ways to support gut recovery worth knowing about.
The takeaway
While no single food or lifestyle habit determines whether someone will develop ulcerative colitis, this review adds to what we know about UC. Many of the factors linked to a lower UC risk (like eating more fruit and enjoying coffee in moderation) also support overall health, making them worthwhile habits regardless.
It's also important to remember that ulcerative colitis is a complex condition shaped by a mix of genetics, environment, and other factors that researchers are still working to understand.