Intestinal bipartition surgery, a newer weight loss procedure that rearranges the intestines, helped 202 Italian patients lose an average of 31% of their total body weight within 12 months, with the most effective technique achieving 42% total weight loss. According to Gram Research analysis, 58.5% of patients saw their high blood pressure disappear, 76% experienced remission of sleep apnea, and only 1.5% experienced serious complications, suggesting this emerging procedure is both effective and relatively safe for severe obesity.
Researchers in Italy studied a newer type of weight loss surgery called intestinal bipartition, which rearranges how food moves through your digestive system. They followed 202 patients who had this surgery between 2019 and 2025 across 13 hospitals. After one year, patients lost an average of 31% of their total body weight, and many saw improvements in health problems like diabetes, high blood pressure, and sleep apnea. The surgery was generally safe, with only 1.5% experiencing serious complications. According to Gram Research analysis, this emerging procedure offers a promising alternative to traditional weight loss surgeries.
Key Statistics
A 2026 retrospective study of 202 patients across 13 Italian hospitals found that intestinal bipartition surgery reduced average BMI from 45.7 to 31.9 within 12 months, representing 30.9% total weight loss and 65.7% excess weight loss.
The Roux-en-Y Transit Bipartition (RYTB) variant achieved superior results, with patients losing 79.7% of excess weight and 41.7% of total body weight at 12 months compared to 64.7% and 29.5% respectively for the OATB/SASI technique.
Among 202 patients undergoing intestinal bipartition procedures, remission rates at 12 months were 76.1% for sleep apnea, 75% for high cholesterol, 58.5% for high blood pressure, and 34.2% for type 2 diabetes, with an additional 50% showing improvement in diabetes control.
Early complications occurred in 9.9% of patients undergoing intestinal bipartition surgery, with major complications requiring intervention in only 1.5% and a readmission rate of 2.5%, indicating a favorable safety profile.
The Quick Take
- What they studied: How well a newer type of weight loss surgery works, comparing three different surgical techniques that rearrange the intestines to help people lose weight and improve their health
- Who participated: 202 patients from 13 hospitals across Italy who had intestinal bipartition surgery between July 2019 and November 2025. The average patient weighed about 300 pounds and had a BMI (body mass index) of 45.7, which is considered very obese
- Key finding: After 12 months, patients lost an average of 31% of their total body weight. The most effective version of the surgery (RYTB) resulted in patients losing 42% of their excess weight, compared to 65% for the other main technique. Additionally, 58.5% of patients with high blood pressure saw it go away completely, and 76% of patients with sleep apnea experienced remission
- What it means for you: If you’re considering weight loss surgery, this research suggests intestinal bipartition procedures are effective and relatively safe options. However, this is early data from just 12 months of follow-up. Talk with your doctor about whether this surgery is right for you, as it’s still considered newer and may not be available everywhere
The Research Details
This was a retrospective multicenter observational study, which means researchers looked back at medical records from 202 patients who had already undergone surgery at 13 different hospitals in Italy. The patients received one of three variations of intestinal bipartition surgery: RYTB (Roux-en-Y Transit Bipartition), OATB/SASI (One Anastomosis Transit Bipartition), or DITB (Duodeno-Ileal Transit Bipartition). All surgeries were performed between July 2019 and November 2025.
The researchers measured how much weight patients lost at 3, 6, and 12 months after surgery using several metrics: changes in BMI (body mass index), percentage of excess weight loss, and percentage of total weight loss. They also tracked whether patients’ weight-related health problems improved or went away completely, including high blood pressure, type 2 diabetes, sleep apnea, and high cholesterol. Finally, they recorded any complications that occurred during or after surgery.
This type of study is useful for understanding how procedures work in real-world settings across multiple hospitals, rather than in a controlled research environment. However, because it’s retrospective and observational, it can’t prove cause and effect as definitively as a randomized controlled trial could.
Intestinal bipartition is a relatively new surgical approach that works differently than traditional weight loss surgeries. Instead of just making the stomach smaller, these procedures also rearrange the small intestines to change how the body absorbs nutrients and responds to food. Understanding how well this newer approach works in real hospitals across a whole country helps doctors decide which surgery to recommend to patients. It also helps identify which surgical variation might work best for different people
This study has several strengths: it includes 202 patients from 13 different hospitals, making the results more representative of real-world practice than a single-center study would be. The researchers tracked patients for a full year, which is long enough to see meaningful weight loss results. However, the study also has limitations. It’s retrospective, meaning researchers relied on existing medical records rather than carefully tracking patients prospectively. There’s no comparison group of patients who didn’t have surgery, so we can’t say definitively that the surgery caused the weight loss (though it almost certainly did). Additionally, 12 months is still relatively early follow-up for weight loss surgery, and longer-term results may differ
What the Results Show
The primary finding was substantial weight loss across all three surgical techniques. Starting with an average BMI of 45.7 (considered very obese), patients’ BMI dropped to 31.9 after 12 months. In terms of excess weight loss (the amount of weight above a healthy range), patients lost an average of 65.7% of their excess weight. When measuring total weight loss (all weight lost regardless of starting point), patients lost an average of 30.9% of their total body weight.
The three surgical techniques showed different levels of effectiveness. The RYTB procedure (Roux-en-Y Transit Bipartition) achieved superior results, with patients losing 79.7% of their excess weight and 41.7% of their total body weight. The OATB/SASI procedure (One Anastomosis Transit Bipartition/Single Anastomosis Sleeve-Ileal bypass) was less aggressive but still effective, with patients losing 64.7% of excess weight and 29.5% of total body weight. The DITB procedure results were not separately detailed in the abstract.
Beyond weight loss, patients experienced significant improvements in weight-related health problems. High blood pressure went into remission in 58.5% of patients. Type 2 diabetes improved in 50% of patients and went into complete remission in 34.2%. Sleep apnea, a serious breathing disorder, resolved in 76.1% of patients. High cholesterol improved in 75% of patients. These improvements are clinically meaningful because they reduce the risk of heart disease, stroke, and other serious health complications.
The safety profile of these procedures was favorable. Early complications (problems occurring within the immediate postoperative period) happened in only 9.9% of patients. Major complications, defined as serious problems requiring intervention (Clavien-Dindo grade 3b or higher), occurred in only 1.5% of patients. The readmission rate was 2.5%, meaning very few patients needed to return to the hospital after discharge. These rates compare favorably to traditional weight loss surgeries, suggesting that intestinal bipartition procedures are relatively safe options
Intestinal bipartition represents an evolution in weight loss surgery. Traditional gastric bypass and sleeve gastrectomy have been performed for decades and have well-established safety records and weight loss outcomes. This newer approach combines elements of sleeve gastrectomy (removing part of the stomach) with intestinal rearrangement to enhance stimulation of the ileum (the last part of the small intestine). The weight loss results reported here (65.7% excess weight loss at 12 months) are comparable to or potentially better than traditional bypass surgery, while the complication rates appear favorable. However, long-term data beyond 12 months is needed to fully compare these procedures to established techniques
Several important limitations should be considered. First, this is a retrospective study looking back at medical records rather than prospectively following patients forward, which can introduce bias in data collection. Second, there is no control group of patients who didn’t have surgery, so while weight loss almost certainly resulted from the surgery, we can’t quantify exactly how much. Third, the follow-up period is only 12 months, which is relatively short for weight loss surgery. Patients’ weight and health improvements may change over longer periods. Fourth, the study doesn’t provide detailed information about patient selection criteria or why different surgical techniques were chosen for different patients, which could affect the results. Finally, the study is from Italian centers, so results may not apply equally to other populations with different genetics, dietary habits, or healthcare systems
The Bottom Line
For people with severe obesity (BMI over 40, or BMI over 35 with weight-related health problems), intestinal bipartition procedures appear to be an effective and relatively safe surgical option. The evidence is strong that these procedures produce significant weight loss and improve weight-related health conditions. However, this is early data from 12 months of follow-up. Before considering surgery, discuss with your doctor whether you’ve tried medical weight loss approaches, whether you’re a good surgical candidate, and which surgical technique might be best for you. Confidence level: Moderate to High for short-term weight loss and health improvements; Moderate for long-term outcomes since data beyond 12 months is limited
This research is most relevant to people with severe obesity who have tried other weight loss methods without success, people with obesity-related health problems like diabetes or sleep apnea, and bariatric surgeons deciding which procedures to offer. It’s less relevant to people with mild to moderate weight concerns or those who haven’t tried medical weight loss approaches first. People with certain medical conditions, previous abdominal surgeries, or who are unable to follow post-surgery dietary guidelines should discuss with their doctors whether this surgery is appropriate
Based on this study, most weight loss occurs in the first 12 months after surgery. Patients typically see significant results by 6 months, with continued improvement through 12 months. Health improvements like blood pressure and diabetes control often happen within the first few months as weight decreases. However, this study only followed patients for 12 months, so we don’t know if weight loss continues, stabilizes, or reverses after that point. Realistic expectations should include ongoing dietary changes and exercise for best long-term results
Frequently Asked Questions
How much weight do people lose after intestinal bipartition surgery?
In a 2026 study of 202 patients, people lost an average of 31% of their total body weight within 12 months. The most effective surgical technique (RYTB) achieved 42% total weight loss, while the alternative technique (OATB/SASI) achieved 30% total weight loss.
Does intestinal bipartition surgery cure diabetes and high blood pressure?
The surgery significantly improves these conditions. In the study, 34% of diabetic patients achieved complete remission, with another 50% showing improvement. High blood pressure went away completely in 59% of patients. However, results vary by individual.
What are the risks and complications of intestinal bipartition surgery?
Early complications occurred in 10% of patients, but serious complications requiring intervention happened in only 1.5%. The readmission rate was 2.5%. These rates are favorable compared to traditional weight loss surgeries, though any surgery carries some risk.
How long does it take to see weight loss results after intestinal bipartition?
Most significant weight loss occurs within the first 12 months. Patients typically see noticeable results by 6 months, with continued improvement through 12 months. This study only tracked patients for 12 months, so longer-term results aren’t yet known.
Is intestinal bipartition better than traditional weight loss surgery?
Intestinal bipartition shows comparable or potentially superior weight loss results (66% excess weight loss) compared to traditional bypass surgery, with favorable complication rates. However, it’s newer with less long-term data. The best choice depends on individual factors and your surgeon’s recommendation.
Want to Apply This Research?
- Track weekly weight and BMI measurements, along with monthly measurements of waist circumference. Set a goal to achieve 65% excess weight loss by 12 months post-surgery. Log any changes in weight-related health conditions like blood pressure readings, blood sugar levels, or sleep quality improvements
- Use the app to log daily food intake and water consumption, aiming for high protein intake (typically 60-80 grams daily) as recommended after bariatric surgery. Set reminders for vitamin and mineral supplementation, which is crucial after intestinal rearrangement surgery. Track exercise minutes weekly, gradually increasing from light walking to moderate activity as approved by your surgeon
- Create a dashboard showing weight loss progress toward your 12-month goal, with milestone celebrations at 25%, 50%, and 75% excess weight loss. Monitor trends in weight-related health metrics monthly. Set up alerts if weight gain occurs (more than 5 pounds in a week) to catch potential problems early. Schedule monthly check-ins with your surgical team and log their feedback in the app
This research describes early 12-month results from a real-world study of intestinal bipartition procedures. Weight loss surgery is a serious medical intervention with potential risks and benefits that vary by individual. This information is educational and should not replace consultation with a qualified bariatric surgeon or your primary care physician. Before considering any weight loss surgery, discuss your medical history, current medications, and individual risk factors with your healthcare team. Results shown in this study may not apply to all patients or populations. Long-term outcomes beyond 12 months are not yet available for these procedures.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.