According to Gram Research analysis, a 6-week randomized controlled trial found that the Specific Carbohydrate Diet and Mediterranean Diet produced similar improvements in ulcerative colitis symptoms, with no significant difference between them. Both diets reduced inflammation markers by comparable amounts, suggesting that following any structured, whole-food-based eating plan may help manage mild to moderate ulcerative colitis, though individual results vary considerably.
Researchers compared two popular eating plans—the Specific Carbohydrate Diet and the Mediterranean Diet—to see which one worked better for people with ulcerative colitis, a condition that causes inflammation in the colon. In this small 6-week study with 17 adults, both diets helped reduce symptoms about equally, with no clear winner between them. However, the study had a major problem: more than half the participants dropped out before it finished, which makes the results less reliable. The findings suggest both diets may be worth trying, but more research with larger groups is needed to know for sure.
Key Statistics
A 2026 randomized controlled trial of 17 adults with ulcerative colitis found that both the Specific Carbohydrate Diet and Mediterranean Diet reduced symptom scores by similar amounts over 6 weeks, with no statistically significant difference between the two approaches.
In a 2026 feeding trial comparing two diets for ulcerative colitis, more than half of the 17 participants (52.9%) dropped out before completion, indicating that maintaining these restrictive diets long-term may be challenging for many patients.
A 2026 study of 17 ulcerative colitis patients found that those following the Specific Carbohydrate Diet showed enrichment of Parasutterella excrementihominis bacteria by week 10, though the clinical significance of this change remains unclear.
The Quick Take
- What they studied: Whether the Specific Carbohydrate Diet or Mediterranean Diet works better at reducing symptoms in people with mild to moderate ulcerative colitis
- Who participated: 17 adults with ulcerative colitis were split into two groups: 8 people tried the Specific Carbohydrate Diet and 9 people followed the Mediterranean Diet for 6 weeks
- Key finding: Both diets reduced inflammation symptoms by similar amounts (Specific Carbohydrate Diet improved by 0.8 points, Mediterranean Diet by 1.3 points on a symptom scale), with no meaningful difference between them
- What it means for you: If you have ulcerative colitis, either diet might help ease your symptoms, but this small study can’t prove one is definitely better. Talk to your doctor before making major diet changes, and remember that what works best varies from person to person
The Research Details
This was a randomized controlled trial, which is considered one of the strongest types of medical research. Researchers randomly assigned 17 adults with ulcerative colitis to follow either the Specific Carbohydrate Diet or the Mediterranean Diet for 6 weeks. The Specific Carbohydrate Diet focuses on simple carbohydrates and avoids grains, while the Mediterranean Diet emphasizes vegetables, fish, olive oil, and whole grains. Researchers measured how much participants’ symptoms improved using a standard scoring system called the partial Mayo Clinic score, which tracks things like bowel movements and blood in stool.
The study was designed as a “feeding trial,” meaning researchers provided or carefully controlled the food participants ate, which helps ensure they actually followed the diet correctly. This is better than just asking people to follow a diet on their own, since people often don’t stick to diets perfectly. The researchers also collected stool samples to look at the bacteria living in participants’ guts, since diet affects which bacteria thrive in your digestive system.
This research approach matters because ulcerative colitis is a serious condition that affects millions of people, and many patients want to know if diet changes can help. By randomly assigning people to different diets and measuring specific outcomes, researchers can get clearer answers than if they just asked people about their own experiences. The feeding trial design is especially important here because it removes the guesswork about whether people actually followed the diets.
This study has both strengths and significant weaknesses. The main strength is that it was a randomized controlled trial with a feeding component, which is a rigorous design. However, the study was very small (only 17 people), and more than half the participants dropped out before it finished (9 out of 17). This high dropout rate is a major red flag because it suggests the diets may have been hard to follow, and the remaining participants might not represent all people with ulcerative colitis. The study was also stopped early, which means researchers didn’t collect as much data as originally planned. These limitations mean we should be cautious about trusting the results until larger, better-completed studies confirm them.
What the Results Show
The main finding was that both diets helped reduce ulcerative colitis symptoms, but they worked about equally well. People on the Specific Carbohydrate Diet improved by 0.8 points on the symptom scale, while those on the Mediterranean Diet improved by 1.3 points. This difference was not statistically significant, meaning it could easily have happened by chance with such a small group.
When researchers looked at secondary outcomes—other measures of health like quality of life and other inflammation markers—they found no meaningful differences between the two diets either. This suggests that for mild to moderate ulcerative colitis, the choice between these two diets may not matter as much as simply following a structured eating plan.
The researchers also analyzed the bacteria in participants’ stool samples. They found that people on the Specific Carbohydrate Diet had more of a specific bacteria called Parasutterella excrementihominis by week 10. We don’t yet know if this bacteria change is helpful, harmful, or just a side effect of the diet.
Beyond the main symptom measurements, the study looked at other health markers but found no significant differences between the two diets. These included measures of inflammation in the blood and overall quality of life scores. The fact that both diets showed similar benefits across multiple measures suggests that the act of following a structured, whole-food-based diet might be more important than which specific diet you choose.
This is one of the first head-to-head comparisons of these two specific diets in ulcerative colitis patients. Previous research has suggested that both diets individually might help some people with inflammatory bowel disease, but this study is among the first to test them against each other in a controlled way. The results align with growing evidence that multiple dietary approaches can help manage ulcerative colitis, rather than there being one perfect diet for everyone.
This study has several important limitations that readers should understand. First, it’s very small—only 17 people completed at least part of the study, which is too small to draw firm conclusions. Second, more than half the participants dropped out, which is a huge problem because it suggests the diets were difficult to follow or didn’t work well enough for people to stick with them. Third, the study only lasted 6 weeks, which may not be long enough to see the full effects of diet changes. Fourth, the study was stopped early, meaning researchers didn’t collect all the data they originally planned. Finally, the study didn’t have a control group eating a regular diet, so we don’t know if these diets are actually better than just eating normally.
The Bottom Line
Based on this limited evidence, both the Specific Carbohydrate Diet and Mediterranean Diet appear to be reasonable options for people with mild to moderate ulcerative colitis, though the evidence is weak due to the small study size and high dropout rate. The Mediterranean Diet has stronger overall health benefits supported by decades of research, so it might be a safer first choice. However, individual responses vary greatly, so what works best depends on your personal situation. Always work with your doctor or a dietitian before making major diet changes, especially with a condition like ulcerative colitis.
This research is most relevant to adults with mild to moderate ulcerative colitis who are interested in dietary approaches to managing their symptoms. People with severe ulcerative colitis should focus on medical treatment first. The findings may also interest people with other inflammatory bowel conditions, though more research is needed in those populations. People without ulcerative colitis shouldn’t assume these diets will help them, since they were designed specifically for this condition.
If you try one of these diets, you should expect to wait at least 2-4 weeks to notice any symptom improvement, though some people may see changes sooner. The study measured changes over 6 weeks, so that’s a reasonable timeframe to give a diet a fair trial. However, individual responses vary widely—some people improve quickly while others see no benefit. Keep a symptom diary to track your progress, and discuss results with your doctor after 4-6 weeks.
Frequently Asked Questions
Does the Specific Carbohydrate Diet work better than the Mediterranean Diet for ulcerative colitis?
A 2026 study found no significant difference between the two diets for reducing ulcerative colitis symptoms. Both showed similar improvements, suggesting either diet may help, but individual responses vary. Talk to your doctor about which approach suits your situation best.
How long does it take to see improvement from changing your diet with ulcerative colitis?
The study measured changes over 6 weeks, which appears to be a reasonable timeframe. However, some people may notice symptom improvement within 2-4 weeks, while others take longer. Keep a symptom diary to track your personal response.
Is the Mediterranean Diet safe for people with ulcerative colitis?
Yes, this study found the Mediterranean Diet was safe and helpful for mild to moderate ulcerative colitis. It emphasizes whole foods like vegetables, fish, and olive oil, which are generally well-tolerated. However, individual tolerance varies, so work with your doctor to personalize it.
Why did so many people drop out of this ulcerative colitis diet study?
More than half the participants (52.9%) dropped out, likely because the restrictive diets were difficult to follow long-term. This high dropout rate suggests these diets may be challenging to maintain, which is important to consider before starting one.
Can diet alone treat ulcerative colitis without medication?
This study shows diet can help reduce symptoms in mild to moderate cases, but it shouldn’t replace medical treatment. Always work with your gastroenterologist to develop a complete treatment plan combining diet, medication, and lifestyle changes as needed.
Want to Apply This Research?
- Track daily bowel movement frequency and presence of blood in stool, plus a symptom severity score (1-10) each day. This mirrors the Mayo Clinic scoring system used in the study and gives you objective data to share with your doctor.
- Use the app to plan and log meals following either the Mediterranean or Specific Carbohydrate Diet approach. Set reminders for meal prep, track which foods trigger symptoms, and identify patterns between what you eat and how you feel over the following 24 hours.
- Create a 6-week baseline measurement period, then implement your chosen diet while the app tracks daily symptoms, meals, and any changes. Generate weekly reports comparing your symptom scores to identify trends. After 6 weeks, review the data with your healthcare provider to decide if the diet is working for you personally.
This article summarizes research findings and should not be considered medical advice. Ulcerative colitis is a serious medical condition requiring professional medical care. Before making any significant dietary changes, especially if you have ulcerative colitis or other digestive conditions, consult with your doctor or a registered dietitian. This study was small and had significant limitations (high dropout rate, early termination), so results should be interpreted cautiously. Individual responses to dietary interventions vary greatly, and what works for one person may not work for another. Always work with your healthcare team to develop a personalized treatment plan.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.