Observing people who fast during Ramadan does not prove that fasting makes ulcerative colitis worse, because other factors like changes in sleep, medication use, or diet during that time could also affect symptoms.

People with ulcerative colitis who fast during Ramadan may experience worse symptoms, but this is not due to increased inflammation in the body, since standard inflammation markers do not change. Other factors like changes in when medications are taken, sleep patterns, or diet may be responsible.

Adults aged 30 and older with ulcerative colitis may have more severe symptoms during Ramadan fasting than younger adults with the same condition, even when accounting for differences in medication or how long they've had the disease.

In people with ulcerative colitis or Crohn’s disease, fasting during Ramadan for one month does not lead to measurable changes in two biomarkers of inflammation: C-reactive protein in the blood and calprotectin in the stool.

In patients with ulcerative colitis, fasting during Ramadan for 14 to 15 hours per day is linked to a small but measurable increase in disease activity symptoms, especially in individuals aged 30 or older or those with higher baseline levels of fecal calprotectin, without corresponding changes in blood or stool markers of inflammation.

During Ramadan fasting, people with ulcerative colitis may experience worsening symptoms, while those with Crohn’s disease typically do not show a change in symptoms, suggesting that fasting affects these two conditions differently.