Researchers tested whether bromelain, a natural enzyme found in pineapples, could help people with ulcerative colitis—a condition that causes inflammation in the colon. Seventy patients with mild-to-moderate ulcerative colitis took either bromelain supplements or a placebo for eight weeks. The bromelain group showed significantly better improvement in disease symptoms compared to the placebo group. However, the supplement didn’t improve overall quality of life scores as much as expected. While these results are promising, more research is needed before bromelain can be recommended as a standard treatment.

The Quick Take

  • What they studied: Whether taking bromelain (an enzyme from pineapples) could reduce inflammation and improve symptoms in people with ulcerative colitis, a chronic digestive disease.
  • Who participated: Seventy adults with mild-to-moderate ulcerative colitis were randomly split into two groups. One group took bromelain supplements while the other took a placebo (fake pill) for eight weeks.
  • Key finding: People taking bromelain showed significantly greater improvement in disease activity scores (dropping 3.29 points) compared to the placebo group (dropping 1.11 points). This difference was statistically significant, meaning it’s unlikely to be due to chance.
  • What it means for you: Bromelain may help reduce ulcerative colitis symptoms, but it’s still experimental. Don’t replace your current medications without talking to your doctor. This research suggests bromelain could be a helpful addition to treatment, but more studies are needed to confirm safety and effectiveness.

The Research Details

This was a randomized, triple-blind, placebo-controlled trial, which is one of the strongest types of medical studies. Triple-blind means the patients, doctors, and researchers analyzing the data didn’t know who received bromelain versus placebo, reducing bias. Seventy patients with mild-to-moderate ulcerative colitis were randomly assigned to receive either 400 mg of bromelain daily or a placebo (maltodextrin powder) for eight weeks. Researchers measured disease activity using a scoring system called the Simple Clinical Colitis Activity Index (SCCAI) and assessed quality of life through questionnaires at the beginning and end of the study.

The triple-blind design is important because it prevents expectations from influencing results. By randomly assigning patients and using a placebo control, researchers could determine whether bromelain actually works or if improvements were just due to the placebo effect. This rigorous approach makes the findings more trustworthy than studies without these safeguards.

Strengths: The study used a strong research design with random assignment and blinding, published in a reputable journal (Scientific Reports), and was registered before starting. Limitations: The sample size of 70 is relatively small, the study only lasted eight weeks, and it only included people with mild-to-moderate disease, so results may not apply to those with severe ulcerative colitis.

What the Results Show

The main finding was that bromelain significantly reduced disease activity compared to placebo. Patients taking bromelain improved by an average of 3.29 points on the disease activity scale, while placebo patients improved by only 1.11 points—a difference that was statistically significant. This suggests bromelain has a real effect beyond placebo. The improvement remained significant even after researchers adjusted for baseline differences between groups. This is important because it shows the benefit wasn’t just due to random variation or differences in how sick people were at the start.

Surprisingly, quality of life scores improved similarly in both groups (3.76 points for bromelain versus 3.91 for placebo), with no significant difference. This suggests that while bromelain reduced measurable inflammation, it didn’t translate into greater improvements in how patients felt day-to-day. The study also found that vitamin B6 intake changed differently between groups, though the clinical significance of this is unclear.

This is one of the first rigorous studies testing bromelain specifically for ulcerative colitis. Previous research suggested bromelain has anti-inflammatory properties, but most studies were in test tubes or animals. This human study provides stronger evidence that bromelain may work in real patients, though the lack of quality-of-life improvement is somewhat unexpected and suggests the benefit may be limited.

The study only lasted eight weeks, so we don’t know if benefits continue longer or if side effects develop over time. Only 70 patients participated, which is a relatively small sample. The study only included people with mild-to-moderate disease, so results may not apply to those with severe ulcerative colitis. The lack of improvement in quality of life raises questions about whether the symptom reduction is clinically meaningful to patients.

The Bottom Line

Bromelain may help reduce ulcerative colitis disease activity (moderate confidence based on this single study). However, it should not replace standard medical treatments. If you have ulcerative colitis, discuss bromelain supplementation with your gastroenterologist before trying it. It may be considered as a complementary therapy alongside your regular medications, not as a replacement.

People with mild-to-moderate ulcerative colitis who are interested in complementary treatments should know about this research. However, those with severe disease, pregnant women, people taking blood thinners, or those with pineapple allergies should avoid bromelain without medical supervision. This research is not relevant to people without ulcerative colitis.

In this study, improvements in disease activity appeared within eight weeks. However, you shouldn’t expect overnight results. If you try bromelain under medical supervision, give it at least 4-8 weeks to see if it helps. Stop and consult your doctor if symptoms worsen or side effects develop.

Want to Apply This Research?

  • Track daily bowel movement frequency and consistency (using the Bristol Stool Scale) along with any abdominal pain or bleeding. Record these metrics weekly to monitor whether bromelain is reducing disease activity over time.
  • If considering bromelain supplementation (with doctor approval), set a daily reminder to take your supplement at the same time each day. Log your supplement intake in the app to maintain consistency and track correlation with symptom improvements.
  • Create a weekly symptom score combining bowel frequency, urgency, and blood in stool to mirror the SCCAI scoring used in the study. Compare your scores month-to-month to objectively assess whether bromelain is helping. Share these tracked metrics with your doctor at regular appointments.

This research is preliminary and should not replace medical treatment for ulcerative colitis. Bromelain supplements can interact with medications and may cause side effects in some people. Do not start bromelain supplementation without consulting your gastroenterologist or healthcare provider. This study involved only 70 patients over eight weeks, so long-term safety and effectiveness are unknown. People with pineapple allergies, those taking blood thinners, or pregnant women should avoid bromelain. Always inform your doctor about any supplements you’re considering.