Medically Reviewed by:Chris Coburn, MD, FRCS(C)Board Certified Bariatric Surgeon
Mini gastric bypass surgery (MGBP) makes the stomach smaller and reroutes the intestines. As a result, patients:
- Feel full sooner while eating
- Absorb fewer calories and minerals
- Lose up to 3/4 of their excess weight within 2 years
- Have significant health improvement
Compared to the more widely performed Roux-en-Y gastric bypass procedure (“gastric bypass”), mini gastric bypass studies show similar weight loss and health improvement, a lower risk of complications, and fewer and less severe side effects (1, 2). Unlike gastric bypass, MGBP is also reversible, and MGBP costs less for self-pay patients.
This page covers everything you need to determine whether mini gastric bypass is the right weight loss procedure for you.
TABLE OF CONTENTS
Click on any of the topics below to jump directly to that section
- How It Works
- Weight Loss
- Health Benefits
- How to Qualify
- Diet & Life After
- Revision Options
- Mini Gastric Bypass Vs Other Procedures
- Start to Finish
- Patient Community & Expert Advice
- Find a Weight Loss Surgeon
- Your reduced stomach size will make you full sooner while eating
- Your intestines that absorb nutrients are shortened, causing the body to absorb fewer calories and minerals
Why Mini Gastric Bypass Works
- Your reduced stomach size will make you feel full sooner while eating
- Your intestines that absorb nutrients are shortened, causing the body to absorb fewer calories and minerals
Preparing for Surgery
During the weeks leading up to mini gastric bypass surgery, your surgeon’s team will do the following:
- Pre-procedure health assessment, where you will be asked questions about your medical history, medications, and surgical history
- Order certain tests like an ECG, x-ray, and blood tests
- Establish a pre-surgery diet regimen, including:
- 2 Weeks Before
- No sugar
- Lower carbs
- Increased protein
- Increased veggies
- Plenty of fluids
- Protein shakes may be prescribed by your surgeon as an alternative
- Day Before
- Clear liquids, broth, one protein shake per day only
- Talk with your surgeon about whether you should stop taking any medications
- From midnight the night before surgery
- No food or drink, no tobacco
- 2 Weeks Before
Losing as much weight as possible prior to surgery is also critical because:
- The more weight you lose pre-op, the more weight you will lose after surgery
- The lower your pre-op weight, the lower your risk of complications
- Mini gastric bypass surgery will not work over the long-term if you slip back into old habits. The sooner you can start establishing good diet and exercise habits, the more likely you will be to maintain them after surgery.
See our Preparing for Weight Loss Surgery page for more information.
How It’s Performed
As the name suggests, mini gastric bypass surgery is a simplified form of Roux-en-Y (RNY) gastric bypass surgery. It takes about 1.5 hours to complete (3).
The procedure serves 2 functions: it limits how much you can eat before feeling full (“restrictive”) and it prevents your body from absorbing as many calories and minerals (“malabsorptive”).
During the laparoscopic procedure, your surgeon will:
- Reduce the size of the stomach by 75%. Leave the remainder of the stomach attached to the top of the small intestines.
- Attach the new stomach about 6 feet down the small intestines to bypass the upper portion of the small intestines and to allow the digestive juices produced by the stomach to “meet up” with food further down the intestines.
Take a look at the following two videos for a more in-depth understanding…
- You can lose up to 75% of your excess weight within 1 year
Mini gastric bypass patients usually lose a lot of weight very quickly, and they tend to keep the weight off over the long term:
- Average 3 months weight loss: One-third of excess weight
- Average 1 year weight loss: 2/3 to 3/4 of excess weight
Many patients reach “peak” weight loss between one and two years, then gain a little back (more about weight regain in the “Downsides” section below). But long-term results are still impressive, with the average patient keeping over 70% of their excess weight off at 10 years post-op(4).
Keep in mind that these are averages – “middle of the road” results. Patients who eat the right foods, exercise regularly, and follow their surgeon’s advice can lose even more, while patients who veer off-track lose less.
Tap here to expand a table of excess weight loss after mini gastric bypass.
- Cures or improves diabetes, sleep apnea, hypertension, and at least 12 other conditions
Most mini gastric bypass patients experience significant improvement in or a complete “cure” of obesity-related health problems.Click Here to See A Full List of Health Benefits
Following are the health improvement statistics for Roux-en-Y (RNY) gastric bypass surgery. There is less published MGBP research, but it is plentiful enough to confirm that weight loss and health benefits for mini gastric bypass surgery are at least as favorable as RNY gastric bypass.
- Mortality Reduction/Life Expectancy (5 year mortality) – 89% reduction in risk of death vs obese patients who did not have bariatric surgery (5)
- Quality of Life Improvements – 95% of patients (6)
- Asthma – Completely resolved or improved in 80% to 100% of patients (7)
- Cardiovascular Disease – Up to 79% reduction in cardiovascular risks (8)
- Degenerative Joint Disease – Complete resolution in 43% of patients (9)
- Depression – Improvement for majority of patients (10)
- Diabetes – 83% experience complete resolution by 1 year (11)
- Dyslipidemia hypercholesterolemia – 63% resolved (12)
- Gastroesophageal Reflux Disease (GERD) – Completely resolved or improved in 80% to 100% of patients (13)
- High Blood Pressure (hypertension) – Up to 69% of patients experience complete resolution by 1 year (14, 15)
- Hyperlipidemia (high levels of fat in the blood) – 73% experience improvement or complete resolution (16)
- Metabolic Syndrome – 80% resolved (17)
- Migraines – 57% resolved (18)
- Non-Alcoholic Fatty Liver Disease – 90% improved steatosis, 37% resolution of inflammation, 20% resolution of fibrosis (19)
- Obstructive Sleep Apnea – Up to 98% resolved (20, 21)
- Polycystic Ovarian Syndrome – Improvement or resolution in nearly all women (22, 23)
- Pregnancy (24)
- Infertility – Obesity-related infertility resolved in up to 100% of women (25)
- Menstrual irregularities – reduced by 65%.
- Gestational Diabetes – 25% less likely to develop
- Pregnancy-Induced Hypertension – 73% less likely to develop
- Pseudotumor cerebri – 96% resolved (26)
- Stress Urinary Incontinence – Up to 88% resolved (27)
- Venous Stasis Disease – Resolved in up to 95% of patients (28)
Mini gastric bypass weight loss improves joint health. For every pound of weight lost, there is a 4 pound reduction in pressure on the knee (29). This improves mobility and reduces pain in the knees.
88,000 participants were involved in data collection on cancer research. Results state that patients who undergo weight loss surgery have 33% less risk of developing cancer (30).
Risk rates were even further reduced for obesity-related cancers, including (31):
- Colon cancer
- Postmenopausal breast cancer
- Endometrial cancer
- Pancreatic cancer
- 35+ BMI with health issues
- 40+ without health issues
Most surgeons follow the guidelines of the National Institutes of Health (NIH) which state that you must fall into one of the following categories in order to qualify for mini gastric bypass surgery:
- Have a body mass index (BMI) of 40 or more (“morbidly obese” or “super obese”), OR
- Have a BMI above 35 (“severely obese”) and have a serious obesity-related health problem (although it may also be appropriate for some patients with a BMI as low as 30)
Serious obesity-related health problems most commonly include:
- High blood pressure
- High cholesterol
- Type 2 diabetes
- Sleep apnea
Other qualifying health conditions related to obesity are listed in the Health Benefits section above.
If you do not meet either of these BMI requirements, you still might qualify for other types of weight loss procedures such as Lap Band or Gastric Balloon.
- Total Cost: $15,000 - $25,000
- Loan Payment: $445/month, on average
- Insurance: Not covered
- Discounts & Tax Savings: Usually available
Unlike Roux-en-Y gastric bypass, mini gastric bypass surgery is not usually covered by insurance, despite being equally if not more effective. This is likely due to fewer surgeons performing the procedure, less published research, and less pressure put on government-sponsored, employer-sponsored, and private health plans to add the procedure to their plans.
On average, the self-pay cost of mini gastric bypass equals:
- United States – $15,000 – $25,000 USD
- Canada – $19,000 CAD
- Mexico – $6,400 – $10,000 USD
- Australia – $23,100 AUD
- United Kingdom – £10,000
However, your out-of-pocket costs depend on several factors including:
- The hospital where your procedure is performed (some hospitals are more expensive than others, which does not necessarily mean better care)
- Whether you obtain financing for some or all of the costs
- Specific fees your bariatric surgeon and other professionals charge for the various pre-op, surgical, and post-op services.
Note that the above averages include total costs incurred during surgery. Some surgeons also include Pre-Op costs in their quoted fees (more on Pre-Op and Post-Op fees below).
However, the above averages do not include Post-Op costs which will be based on your specific circumstances.
Total surgery costs can be further complicated by:
- Discounts – Discounts may be offered for things like full up-front payment. Ask your surgeon’s office if there are any other discounts that you might be able to take advantage of.
- Same Surgeon, Different Hospitals – Some surgeons have “operating privileges” at more than one hospital. Since hospital costs can vary widely – even in the same town and regardless of quality – ask your surgeon if you have a choice.
Mini gastric bypass fees are split between Pre-Op, Surgery, and Post-Op services:
- Pre-Op (Costs Before Surgery) – vary depending on where you live
- Physician-supervised weight loss program (may be required prior to surgery approval)
- Dietitian/nutritionist consultations
- Psychologist (mental health clearance)
- Cardiologist (heart health clearance)
- Lab/blood work, echocardiogram (also known as an “ECG” or “EKG”) and/or X-Ray fees
- Surgeon consultation fees
- Sleep study
- Costs During Surgery
- Hospital fees
- Surgeon fees
- Surgical assistant fees
- Anesthesia fees
- Operating room fees
- Post-Op (Costs After Surgery)
- Addressing any complications
- Follow-up doctor visits
- Bariatric vitamins
- Additional food costs (healthier food tends to cost more)
- Personal trainer and/or gym membership
- New clothes (wait to go crazy with this until you reach your plateau weight)
- Plastic surgery to address sagging skin (more on this in the Downsides section below)
Mini Gastric Bypass Costs Vs. Cost of Not Having Surgery
While mini gastric bypass surgery can be costly, the long-term costs of obesity-related health problems for people who don’t get the surgery are even higher.
Compared to morbidly obese people who don’t have surgery, weight loss surgery patients pay off their entire surgery and start getting ahead financially after only 2 years (32).
Fewer prescription drugs alone have been found to save patients $3,000 or more per year (33).
A study published by the American Journal of Managed Care (AJMC) found that bariatric patients pay as much as $900 less per month as soon as 13 months after surgery than similar people who didn’t have surgery (34). That’s almost $11,000 per year in total medical costs saved for bariatric patients versus morbidly obese people who do not have surgery.
Mini gastric bypass financing is available in most locations.
Options for making surgery more affordable include (follow links for more information):
- Payment Plan Through a Qualified Bariatric Surgeon – This is probably your most realistic and affordable local non-insurance option
- Brokers, Direct Lenders and Credit Cards (Unsecured Medical Loans)
- Friends & Family
- Secured Medical Loans
- Retirement Plan Loans
- Permanent Life Insurance Loans
- Medical travel – having surgery in a location that is less expensive than where you live
Taxes: Several Ways to Save
Most countries provide tax benefits to mini gastric bypass patients who qualify.
United States: Might Be Deductible
Mini gastric bypass surgery is tax deductible as long as the costs are higher than 10% of your adjusted gross income (click here for IRS rules).
In order to receive the deductions, you’ll need to complete Schedule A of the IRS Form 1040. You’ll also need to save your medical bills and payment statements as proof. Note that any reimbursed amounts cannot be included (such as the amount that insurance paid).
Depending on your employment status, money accrued in special savings accounts (or even your IRA) could also be a tax-advantaged payment option. Special tax-favored accounts to consider include:
- Health Savings Account (HSA) – HSAs can only be opened alongside a “qualified high deductible” health plan. Money contributed to an HSA, accumulated interest from the accounts where the money is invested, AND money taken out of the HSA to pay for qualified medical expenses are all TAX FREE. No other account receives more favorable tax treatment. You may even be able to transfer money already in your IRA into an HSA. See the IRS’s Site for more info.
- Archer Medical Savings Account (Archer MSA) – Archer MSAs are very similar to HSAs, except they are for self-employed individuals or small businesses.Click here for the details.
- Health Reimbursement Account (HRA) – HRAs can only be offered by your employer, and only your employer can contribute money to them. If your company offers one, make sure your plan allows the use of HRA funds to pay for “all qualified medical expenses” as financing bariatric surgery is not allowed with some plans. More information can be found by clicking here.
- Flexible Spending Account (FSA) – Both employers and employees can contribute to an FSA, also known by its IRS code, “Section 125”. FSA’s can be offered alongside any health plan, and withdrawals from this account can be made tax-free as long as they are used to pay for qualified medical expenses. Click here to get the summary from the IRS.
Canada: Is Deductible
Canada is generous compared to other countries when it comes to medical tax deductions. As long as you can substantiate your out of pocket mini gastric bypass expenses with a prescription, receipt, or other documentation, you should be able to write them off.
If your income is below a certain threshold, you may qualify for a tax credit called the refundable medical expense supplement.
Contact your provincial Ministry of Health for more details.
Australia: Might Be Deductible
If your out of pocket expenses for bariatric surgery (and all other net medical expenses) are over the Australian Taxation Office (ATO) threshold, you can claim an offset on your tax return.
According to the ATO:
“To claim the net medical expenses tax offset in your tax return, you will need to know the total medical expenses you incurred for yourself and your dependants. You then deduct any refunds from Medicare, your health fund or any other reimbursements that relate to those expenses received during the financial year.”
Click here for updated Medicare Benefit Tax Statement information from the Department of Human Services.
- Hospital Stay: 1 to 2 Days in Hospital
- Time Off Work: 10 to 14 Days
- Full Recovery:
Mini gastric bypass patients usually spend 1 to 2 days in the hospital, and most patients have fully recovered in 2 to 3 weeks (35). Here’s what to expect following surgery:
1. Wake Up
You’ll be sore and a feel a little “out of it.” You’ll be on medication to control the pain.
2. Move Around
Your surgeon will have you up and walking around as soon as possible – usually within 5 or 6 hours – to reduce the risk of blood clots and jumpstart your body’s healing process. You may also be asked to wear compression stockings, use a pneumatic compression device that keeps the blood flowing in your legs, or receive blood thinners. Continue to walk as much as possible, increasing it a little each day.
3. Get Released
Before releasing you, your surgical team will run a number of tests to ensure:
- Wounds are healing properly
- You’re able to “pass gas,” indicating that your digestion is working properly
4. Look for Warning Signs
Fever, no improvement or worsening of pain, signs of incision infection (pus, swelling, heat, or redness), difficulty swallowing, and ongoing nausea or vomiting are all a concern. Call your surgeon immediately if any of these happen.
5. Transition Your Diet
Your smaller stomach will be sensitive, especially at first, so you’ll be on a liquid diet for a couple of weeks before slowly transitioning back to solid foods (read more about this in the Diet section of this page). Since you’ll be eating less, you may feel tired and lethargic until your body adjusts.
6. Ease Off Medications
Your surgeon will prescribe pain and digestion medication as needed and may adjust your pre-surgery medications until you’re fully healed. Follow their instructions to the letter.
7. Return to Your “New Normal” Life
Avoid swimming or bathing until your incisions have fully healed. Many patients return to normal life and work within a couple of weeks, but plan for up to 2 to 3 weeks off to be on the safe side. Full exercise and heavy lifting typically resume within one to two months. Due to your smaller walnut-sized stomach, you will feel full much sooner than you did before surgery. To avoid stretching your new stomach which can lead to weight regain, do not overeat.
8. Have Follow-Up Visits During First Year
Follow-ups may occur with your surgeon or primary care physician and are recommended about one week post-op, then 4 weeks post-op, then every 3 or 4 months to ensure that everything is on track, including:
- Discuss weight loss
- Encourage regular exercise
- Obtain lab work and make necessary adjustments to medications and dietary supplements
- Understand diet and identify any potential eating disorders
- Determine whether any potential complications may be arising
- Monitor status of obesity-related health issues
- Involve your family physician to help evaluate progress and ensure a successful transition
9. Transition to Semi-Annual or Yearly Follow-Up Visits
After you’ve reached your “low point” weight, your surgeon will probably still want to see you at least once per year (36). During those visits you may meet with several team members, including your surgeon, dietitian, and mental health care provider. They will probably request lab work to ensure that vitamin levels and other indicators are where they should be. If you experience any issues in between visits, don’t wait for your next visit… call your doctor right away.
- Most patients experience significant & rapid weight loss
- You will have a restricted diet
- You will feel full sooner
- You will need to supplement with multivitamins
Mini gastric bypass leads to impressive weight loss and health improvement, but what will day-to-day life be like? What are the tradeoffs?
Your surgery is only a tool, and long-term success requires diligence and sometimes difficult change in other areas.
Food & Drink: Significant Changes
Following surgery, it will take about 6 weeks to transition into your new long-term mini gastric bypass diet which includes significant restrictions.
Tap here to expand your diet requirements timeline.
|Timeframe Range||Diet Requirements|
|2+ Weeks Before Surgery||Practice your post-mini-gastric-bypass diet|
Recovering from surgery has its own set of challenges. Do not wait until after surgery to start your new life. Establish the following long-term diet habits ahead of time to:
Long-Term Habits to Begin Before Surgery
|2 Weeks Before Surgery||High protein, low sugar, low carbs|
You will be on a special diet 2 weeks before surgery to reduce the risk of complications.
Add the following to the full ‘2+ Weeks Before’ list above:
The typical 2 week pre-op meal plan includes:
The purpose of this diet is to:
|1 Week Before Surgery||Stop or change some medications|
Your surgeon will ask you to stop taking several medications one week before surgery, such as:
Avoiding these medications will reduce the risk of bleeding and stomach problems after surgery.
Consult with your doctor or pharmacist prior to stopping or changing any of your medications.
|2 Days Before Surgery||Clear liquids only|
You should stop eating all foods and drink only clear liquids during the 2 days before surgery. This will clear out your digestive system before surgery.
Clear liquids options include:
Do NOT consume…
|Midnight Before Surgery to 7 Days After Surgery (Varies by Surgeon)||Nothing to eat or drink|
Your digestive system must be completely free of food or liquids during surgery. This will reduce the risk of breathing in stomach-contents which can cause all sorts of problems like serious infection or pneumonia.
A clean digestive system is especially important for patients with gastroesophageal reflux disease (GERD) or gastric paresis (paralysis of the stomach). (37)
When you brush your teeth before heading to the hospital, rinse and spit out the water (don’t swallow).
|In Hospital (1 -2 Days) thru Day 7 After Surgery||Clear liquids only|
You will transition into drinking “richer” clear liquids along with the following guidelines:
Drinks that your nurse will provide may include:
Your stomach is in healing mode, so go easy on it when you return from the hospital.
Be sure to drink plenty of fluids, but don’t drink too fast. Maintain the same clear liquids only diet that you were on in the hospital.
Take all vitamins and supplements recommended by your surgeon.
If you have no nausea or vomiting, your surgeon may allow you to try thicker items ahead of schedule (see below).
|Day 1 to Week 2 After Surgery (Varies by Surgeon)||Add thicker drinks & smooth foods (no chunks)|
Your healing should be well underway. It’s now time to introduce thicker drinks and pureed foods. As soon as you’re ready, your surgeon will start you on many small “meals” per day which may include:
Remember: No soft or solid food and no drinks with chunks or seeds.
You can also drink clear liquids between meals.
While drinking anything:
|Day 2 to Week 3 After Surgery (Varies by Surgeon)||Slowly test pureed & soft solid foods|
By this point it should be safe to add softer solids to your diet, but take it slow!
When you’re ready to start pureed foods, blend water, skim milk, broth, or sugar-free juice with one of the following:
As soon as the pureed foods are going down without a problem, work your way into soft foods like:
And remember those habits you formed in the weeks and months leading up to surgery? Here’s where they start to come in handy.
General diet guidelines during this stage include:
|Day 3 to Weeks 4+ After Surgery (Varies by Surgeon)||Slowly test solid foods|
Complete your slow transition to your “new normal” long-term diet.
Your focus should be on eating your proteins first, in solid form (not protein shakes). Here’s why:
Other points to consider, besides those reviewed in Day 2 to Week 3 above, include:
For more information, see our Bariatric Diet page.
Vitamins & Supplements: Lifelong & Crucial
Since mini gastric bypass is a “malabsorptive” procedure, it carries a risk of malnutrition. Patients must be extremely diligent about taking prescribed vitamins and supplements or risk vitamin deficiency.
Tap here to expand your list of crucial vitamins & supplements after MGB.
|Vitamins||Body Part Affected|
|Multivitamin (38) (39)||Entire body|
A daily multivitamin with mineral supplements will help with hair loss and general nutrition problems.
Calcium citrate supplements will keep your bones strong.
|Folate (folic acid) (41)||Blood|
Patients who don’t get enough folate are at a higher risk of anemia.
|Iron (42) (43)||Blood|
Patients low in iron are more likely to have a stroke, heart attack, or other blood-related problems.
Some patients may require additional iron, which should be taken with Vitamin C for better absorption. For these patients, Iron supplements must be taken forever.
|Thiamin (Vitamin B1)||Entire Body|
Thiamin deficiency, also called Beriberi, can result in loss of appetite, headaches, nausea, weakness, irritability, depression, abdominal discomfort, pain in the limbs, shortness of breath, and swollen feet or legs
Deficiency may occur after vomiting, skipped meals, or missed supplementation
|Vitamin D (44) (45) (46)||Entire Body|
Without enough Vitamin D, you’re at risk of developing rickets, a weakening of the bones, muscles, and teeth.
Talk with your surgeon to be sure, but you may be able to find a calcium supplement that fulfills your Vitamin D requirements.
|Vitamin B12||Brain/Nervous System|
Your central nervous system relies on Vitamin B12, and not getting enough of it could lead to serious issues like numbness, memory loss or even paralysis.
For more information, see our Bariatric Vitamins page.
Exercise: 2.5 hours per week, spread out over 2 to 4 days
Exercise is almost as important as what you eat after mini gastric bypass surgery for two big reasons:
- Patients who exercise regularly lose more weight over the long-term
- Physical and mental health benefits make you much more likely to keep your new lifestyle requirements in line
How much exercise do you need for noticeable results?
One study found that exercising 2.5 hours per week leads to 5.7% more weight loss (47). Another showed that gastric bypass patients who exercise at least 30 minutes a day, 3 days per week have a 4+% lower body mass index (48).
Further, regular exercise leads to quicker improvement in obesity-related health problems following surgery (49).
To help you stay on track:
- Block out time to exercise at the same times on the same days of the week.
- Spread your workouts over 3 or 4 days each week rather than having one or two long sessions. In addition to building endurance, this will make working out less intimidating.
When choosing your exercise routine, focus on three aspects: endurance, flexibility, and strength. Here are suggestions for each:
- Stationary bike
- Swimming (best option)
- Well-rounded stretching routine, ideally yoga since it incorporates proper breathing and uses your own bodyweight to build strength
- Exercise balls
See our Exercise After Bariatric Surgery page for more information.
Your Brain: Careful About Food Addiction, New Mentality Will Change Behavior & Relationships
Feel Full Sooner
The big diet changes reviewed above may be easier than they sound because your stomach will be much smaller, causing you to feel full much sooner while eating.
If not addressed prior to surgery, food addiction can lead to long-term weight regain for mini gastric bypass patients. If you struggle with food addiction, talk with your surgeon before moving forward with surgery.
To find out if you may be suffering from food addiction, take our Food Addiction Quiz.
Relationships After Weight Loss
Mini gastric bypass leads to rapid and significant weight loss, and people will start treating you differently within a couple of months after surgery. Following are positive experiences reported by most patients:
- Treated with more respect
- More romantic interest from others
- No more obesity discrimination
- Deeper relationships as a result of being able to physically keep up with kids and more physically fit friends
- More compliments from others
- Increased self-confidence
- Improvements in quality of sexual life (50)
However, being “newly thin” may carry unforeseen negatives as well:
- How will overweight friends or family members feel when you’re losing weight but they are not?
- If they’re not making diet and lifestyle changes as well, will your friends or family make it more difficult for you to stay on track?
- How will your coworkers react? Should you even tell them you are having surgery?
- Will your new healthier diet and smaller portion sizes make meals with others awkward?
- Could intimacy with your spouse or partner be effected?
- Could your spouse or partner become jealous now that others are noticing you more?
The way you view people and relationships may change as well. Common thoughts include:
- “Would this person be treating me the same way if I hadn’t lost all of this weight?”
- “How do I handle obesity discrimination now that I’m on the “other side”?”
For real life experiences and advice from other weight loss surgery patients, see our Relationships After Weight Loss surgery page.
- There is a low risk of complications
- Risk of vitamin deficiency
- Side effects may include sagging skin, weight regain, and digestive/diet issues
Mortality rates (risk of dying) for mini gastric bypass are extremely low at close to 0%. The overall complication rate is also very low at less than 5%. (51, 52, 53, 54)
When compared to Roux-en-Y gastric bypass, the unique complication associated with mini gastric bypass is bile reflux into the esophagus. However, it only occurs in fewer than 1 out of every 100 patients (55).
Preventing Mini Gastric Bypass Complications
- Follow these steps to reduce your risk of mini gastric bypass complications:. Different surgeries carry different risks for different people. Our Types of Bariatric Surgery page compares and contrasts the safest and most effective procedures.
- Choose an experienced surgeon, since more experienced surgeons tend to have better outcomes. For example, one study evaluated a surgeon over his first 300 laparoscopic gastric bypass patients. Following were his results as he gained experience (56):
Tap here to expand a table of surgeon performance over time.
As you can see, the more procedures he performed, the lower the time it took to perform the surgery and the lower the number of reoperations required.
A separate and much larger study of over 15,000 patients in Michigan had similar findings (57):
Tap here to expand a table of the study’s results.
# of procedures performed by surgeon over 3 years Rate of serious complications occuring within 30 days of surgery Less than 100 cases 3.8% 100 – 249 cases 2.4% Greater than or equal to 250 cases 1.9%
Most surgeons offer free seminars or consultations that teach you about your weight loss surgery options, their practice’s experience, total procedures performed, and specific results. The seminars also allow you to get to know the surgeon prior to a one-on-one consultation.
You can also review our Bariatric Doctors page to learn how to interview multiple doctors and choose the best one.
- Eat and exercise as directed by your surgeon before, during, and after surgery. Your behavior before and after surgery directly and significantly impacts your mini gastric bypass complication risk. Read the other sections of this page for more information.
Possible Mini Gastric Bypass Complications
The most common complications, which occur in greater than 1% of patients, include:
Marginal Ulcers – About 3% of patients
Marginal ulcers are relatively common after Roux-en-Y gastric bypass, mini gastric bypass, and duodenal switch (Scopinaro procedure). Ulcers can usually be avoided by an appropriate bariatric diet , by not smoking and by staying away from NSAIDs (non-steroidal anti inflammatory drugs, including ibuprofen, Aleve, etc.). You can often tell if you have one because of a burning pain in the stomach. Your doctor can confirm ulcers with an endoscopy (a scope than is inserted through your mouth and down your esophagus) and usually treat them with antacids.
Gastrointestinal bleeding – About 3% of patients
A copious discharge of blood from the blood vessels. After the surgeon determines the type and severity of internal bleeding, it can be resolved in a number of ways: on its own, replenishing bodily fluids, stopping the use of all anticoagulation drugs and (rarely) by transfusion or reoperation.
Wound Infection – About 3% of patients
When incisions are contaminated with a disease-producing substance or agent (such as bacteria). Much more common in open surgeries than in laparoscopic surgeries due to the size of the external incisions. Usually treated with antibiotics.
Gastrointestinal Leak – About 1% of patients
Occurs when sealed or sutured (stitched) openings leak digestive contents into the abdomen. This can cause infection and abscess. Can be repaired as long as it is caught early. Symptoms include fever, severe pain and a high heart rate. In order to prevent leaks, your surgeon should check the surgical connections a number of different ways, including (1) blowing air into the connection and observing whether any gets through and (2) using a dye to check for a leak. Leaks not discovered right away are usually treated by resting the stomach (being fed through an IV), but sometimes surgery is required to fix them.
Bile Reflux Esophagitis – Less than 1% of patients
Occurs when bile backs up into the stomach and esophagus. Symptoms are similar to acid reflux and include upper abdominal pain, heartburn, nausea, or vomiting a greenish-yellow liquid. May require reversal of the MGB procedure or a conversion to a different procedure.
For a full list of potential weight loss surgery issues, see our Weight Loss Surgery Complications page.
Mini Gastric Bypass Side Effects: Digestion/Diet Issues, Sagging Skin, Others
Click below for more information about each mini gastric bypass side effect:
Digestion & Diet Issues
- Hypoalbuminemia – About 10% of patients (58) (same as Roux-en-Y gastric bypass)
Hypoalbuminemia, or low levels of albumin in the blood, includes symptoms range from none to general or local swelling, muscle weakness, fatigue, or cramps. It can be treated by increasing the amount of protein in the diet (59)
- Iron Deficiency Anemia – About 5% of patients (60) (same as Roux-en-Y gastric bypass)
Exists when there are not enough healthy red blood cells as result of insufficient iron in the body. Usually treated successfully with iron supplements.
- Diarrhea or loose stools – usually completely dependent on diet – Since mini gastric bypass is “malabsorptive”, some patients experience diarrhea. To prevent it, you will need to figure out and avoid foods that “trigger” diarrhea. It could also be the result of lactose intolerance (not a side effect of surgery, but surgery can make you more sensitive to a problem that you didn’t know you had) which would require dairy products to be removed from the diet.
- Dumping syndrome after mini gastric bypass surgery is possible but far less likely than after Roux-en-Y gastric bypass (61). Symptoms may include weakness, dizziness, flushing and warmth, nausea and palpitation immediately or shortly after eating. They are caused by abnormally rapid emptying of the stomach especially in individuals who have had part of the stomach removed.
See our Dumping Syndrome page for more details.
- Dehydration – an abnormal depletion of body fluids. You will need to drink a lot of water in the months following surgery – as much as 2 liters per day. Not doing so can lead to nausea and vomiting which can lead to even worse dehydration and other problems. In severe cases of dehydration patients may need to return to the hospital for IV fluids and vitamins.
- Dyspepsia – is the inability to digest or difficulty in digesting food, the incomplete or imperfect digestion of food or a case or attack of indigestion marked especially by a burning sensation or discomfort in the upper abdomen.
Treatment is usually as simple as changing your diet, such as avoiding greasy foods or limiting liquid intake to certain times of day. Alcohol, aspirin and other drugs are also causes. If diet changes don’t work, antacids and H2 blockers are sometimes prescribed.
- Intolerance to certain foods, beverages and drugs – With a changed stomach size and digestive system, there will be certain foods, beverages and drugs that you’ll need to avoid and certain diet habits you’ll need to maintain.It is important to talk with your doctor before taking ANY drugs, as they can damage your smaller stomach after mini gastric bypass surgery and cause ulcers (including over the counter pain relievers – Motrin, Advil, aspirin, Aleve).
Regarding alcohol, a little may still be okay, but it will have a profoundly different effect on your body than it used to. First, it’s bad for your diet due to the large amounts of calories found in many alcoholic beverages. Second, you will become intoxicated more quickly following surgery which could lead to a number of problems.
Finally, following surgery the effects of alcohol on your system could make liver disease more likely. As for smokers, you must stop now. If you smoke after mini gastric bypass surgery, there is a good chance that you will get an ulcer in your stomach.
- Nausea and vomiting – is also possible after mini gastric bypass. Following your doctor’s bariatric diet recommendations exactly will typically fix or improve the problem. While in the hospital, receiving a larger amount of IV fluids at a faster rate may make you less likely to feel nauseous or vomit. Keeping a food journal for a couple of days may help you to pinpoint the foods which seem to cause nausea and vomiting.
Mini gastric bypass surgery causes most patients to lose weight fast, and for some patients, the skin simply can’t keep up. Whether you experience sagging skin depends on how much weight you have to lose, whether you exercise, your age, and if you smoke.
Sagging skin can cause several mental and physical issues including:
- Difficulty getting dressed
- Difficulty exercising, which may impact long-term weight maintenance and health
- Embarrassment with or without clothes on
- Skin fold rashes or breakdown of skin
- Skin fold infections
Options for addressing sagging skin include:
- Body-contouring undergarments
- Plastic surgery to remove the excess skin, which is often covered by insurance. See our Plastic Surgery After Weight Loss page for more information.
Other Potential Side Effects
- Gallstones are small stones of cholesterol formed in the gallbladder or bile passages. They can be created following rapid weight loss which leads to their development in as many as 1/3 of bariatric surgery patients. To prevent this, your surgeon may remove your gallbladder during surgery or prescribe bile salt supplements after surgery.
- Hair loss occurs to some degree for most patients and can be caused by nutritional deficiencies or as your body’s response to major surgery or extreme weight loss. Most patients stop losing and start regrowing hair within 3 to 6 months following surgery. Supplementing your diet with protein, vitamin B, magnesium, calcium and zinc, among other bariatric vitamins, will help prevent hair loss and improve hair growth.
- Kidney stones are stones in the kidney related to decreased urine volume or increased excretion of stone-forming components such as calcium, oxalate, urate, cystine, xanthine and phosphate. The stones form in the urine collecting area (the pelvis) of the kidney and may range in size from tiny to staghorn stones the size of the renal pelvis itself. Drinking lots of water, which gastric bypass patients should do anyway, will help to dilute the urine and may help prevent kidney stones.
Weight Regain: Only 4% Gained Back At 5 Years
The average mini gastric bypass patient regains about 4% of their excess weight at 5 years post-op. Impressively, about 9 out of 10 patients maintain at least 50% excess weight loss at 5 years (62).
Why do patients gain back weight?
Usually it’s because the patient veers off course and consumes foods or beverages they shouldn’t, causing their smaller stomach to stretch out (63).
If you start to gain back weight, contact your surgeon or dietitian immediately to assess your diet and exercise habits.
See our Weight Regain After Bariatric Surgerypage for advice on how to avoid weight regain after mini gastric bypass surgery.
See the Revision section below for options to surgically address weight regain.
- You can convert to a Roux-en-Y gastric bypass
- You can convert to duodenal switch
- You can add the adjustable gastric band
Mini gastric bypass is a relatively simple procedure to reverse or fix. Revision may be recommended by your surgeon in the following circumstances (64):
- Bile Reflux
- Gastrointestinal Leak
- Excessive weight loss/malabsorption
- Inadequate weight loss
To maintain or improve weight loss, your mini bypass revision options include:
- Convert to a Roux-en-Y gastric bypass
- Convert to duodenal switch – more likely to be recommended by your surgeon if you were considered “super obese” (BMI over 50) prior to your initial surgery.
- Add adjustable gastric band (convert to Lap Band surgery)
- Similar or better weight loss & health improvement
- Similar or lower risk of complications and side effects
- Similar or shorter hospital stay and recovery time
- Similar or lower self-pay cost, but not covered by insurance
- Less common
Mini Gastric Bypass Vs. Other High-Weight-Loss Procedures
Compared to the other high-weight-loss procedures (gastric sleeve, gastric bypass, Lap-Band, and duodenal switch), mini gastric bypass surgery:
- Has similar or better long-term weight loss and health improvement
- Has a similar or lower risk of complications and side effects
- Has a similar or shorter hospital stay and recovery time
- Along with Lap Band, is the only other easily reversible procedure
- Is not covered by insurance (the other high-weight-loss procedures are)
- Has similar or lower costs (if you don’t have insurance that covers weight loss surgery)
- Is less commonly performed, probably because Roux-en-Y gastric bypass became popular first and therefore received more attention and research
Mini Gastric Bypass Vs. Gastric Bypass (Roux-en-Y)
Compared specifically to the more widely performed “Roux en Y” gastric bypass procedure, mini gastric bypass surgery is different in that it:
- Is a simpler, less time consuming, and less invasive procedure
- Leaves a larger portion of the stomach attached to the esophagus
- Uses a different configuration for the small intestine (does not separate the top of the small intestine and bypasses more of it; one small intestine anastomosis (connection) instead of two.)
- Allows some digestive juices to flow back into the stomach, which may result in a higher risk of bile reflux gastritis. However, 99 out of 100 MGBP patients do not experience it (65).
- Is much more easily reversed or revised
- Results in at least as much weight loss
- Has a lower risk of complications
- Is not covered by insurance
- Costs less for cash-pay patients
One theory for its lack of widespread availability is that Roux-en-Y gastric bypass was “first out of the gate” and therefore became the go-to procedure. As a result, MGBP has not been performed as frequently as RNY and has fewer studies to back it up.
The slower accumulation of supporting research appears to be reaching a tipping point, and we expect this procedure to gain broader acceptance in the coming years.
Mini Gastric Bypass Positives
- Weight loss is equivalent or better than all procedures other than duodenal switch.
- Health Improvement is equivalent or better than all procedures other than duodenal switch.
- Short-term and long-term risk of complications is lower than gastric sleeve, gastric bypass, and duodenal switch (similar to AspireAssist, higher than gastric balloon).
- There is no external device left inside the body as there is with Lap Band and gastric balloon, so there is no risk of device-related complications.
- Reversible Mini gastric bypass surgery, along with Lap Band, gastric balloon, and AspireAssist, are reversible. This means that if you don’t like it, you can go back to the way things used to be or try another procedure. Gastric sleeve, RNY gastric bypass, and duodenal switch surgery are not reversible – once your stomach size is reduced and your intestines are rerouted, it is very it is very difficult or impossible for those procedures to be reversed.
Mini Gastric Bypass Negatives
- Mini gastric bypass and Roux-en-Y gastric bypass both have a higher risk of hypoalbuminemia (low levels of albumin in the blood) than other procedures. Can often be treated by increasing protein in the diet.
- Vitamin deficiency The three “malabsorptive” procedures, mini gastric bypass, Roux-en-Y gastric bypass and duodenal switch, bypass the top portion of your small intestine, putting patients at a higher risk of vitamin deficiency. Close attention to vitamin levels and strict adherence to a vitamin regimen are a must.
- Not covered by insurance if you have insurance that covers weight loss surgery, mini gastric bypass will probably not be covered (gastric sleeve, Roux-en-Y gastric bypass, Lap Band and duodenal switch will probably be covered).
- Fewer surgeons perform it depending on where you live, it may be difficult to find a surgeon who has experience performing mini gastric bypass surgery. If so, you would need to travel to have the procedure.
- 7 Steps to Long-Term Weight Loss
01. Start Working with a Weight Loss Surgeon As Soon as Possible
Surgeons will help you effectively navigate the various procedure choices, pre-surgery steps, financing, and insurance options:
- As a first step, many surgeons offer a free initial consultation or a free local seminar or webinar to give you a better understanding of what to expect.
- Many will also provide a free insurance check to help you figure out how much insurance will cover, and, if necessary, appeal any denials or find additional financing. Most insurance companies require you to complete a medically supervised diet and exercise program before they will approve your surgery, so your surgeon will set this up for you if you haven’t done so already.
- Your surgeon will also push you towards new habits that will be essential to long-term success after surgery. Many surgeons will recommend that you attend support group meetings so you can listen to feedback from actual patients.
02. 2 Weeks Out: Prepare for Surgery
By 2 weeks out you will have completed your pre-op tests, physical, and any other necessary steps required by your surgeon or insurance company. You should have insurance approval (if applicable), and you should be well on your way towards developing your new long-term lifestyle and diet habits. In the week or two leading up to surgery you’ll be seeing the hospital pre-surgery department for an EKG, blood work, and any last minute instructions or other pre-op tests. You’ll see the surgeon one more time for consents, a pre-operative physical, and any last minute details. The night before surgery you’ll be asked to not eat or drink anything starting at midnight.
03. Surgery Day
You’ll be asked to arrive at the hospital at least two hours prior to surgery to allow for prep time. The mini gastric bypass procedure itself will take about 2 hours to perform. For the first few hours after surgery, you probably won’t be awake to remember it, but you’ll have one-on-one attention from someone on your surgical team to manage your pain and monitor your vitals. Click here for more about what to expect in the hospital.
Most mini gastric bypass patients are in the hospital for 2 or 3 days total. You will probably not be allowed to eat or drink anything for at least 24 hours after surgery, and your surgeon will want you to get up and walk around as soon as possible to start the healing process. You’ll be discharged as soon as your surgeon is confident that you are well on the road to full recovery. You’ll likely need someone to drive you home from the hospital and care for you for at least a few days following surgery. Full recovery generally happens within 4 to 6 weeks. Click here for more about the recovery process..
05. Adjust to Your New Post-Surgery Diet & Lifestyle
Over the course of the first 6 weeks following surgery you will slowly transition from a sugar-free clear liquid diet to your “new normal” mini gastric bypass diet. You should also continue your transition into a more active lifestyle. You will feel full sooner, you may feel less hungry generally, and you should start to experience significant weight loss within a couple weeks. Your surgeon’s dietitian or nutritionist will help you determine an appropriate diet. See the Diet & Life After section of this page for more information.
06. Attend Support Groups Regularly
Regular weight loss surgery support group participation has been found to lead to the following benefits:
- Reduce post-op recovery time
- Lead to as much as 12% more long-term weight loss
Your surgeon will be able to recommend an in-person group near you.
07. Ongoing Doctor Visits
For the first year, your surgeon will most likely schedule follow up visits. Shortly after surgery, they will be weekly then transition to every four weeks, and, later, once every few months to ensure that you are recovering well and to answer any questions you may have. Subsequent doctor visits will be scheduled on an as-needed basis along with annual check-ups.
- You can read about the experiences of other mini-gastric bypass patients
- You Can "Ask the Expert"
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Why is mini gastric bypass surgery not more popular? Is there some inherent problem with it? Based on all of the research I've done, it seems to be a great…Is Mini Gastric Bypass Surgery a Good Option?*
I am considering mini gastric bypass surgery. I have a BMI of around 35 or 36, my weight is 85 kgs (187 lbs) and I am 45 years old. I've…Weight loss will not stop after mini gastric bypass surgery*
I am a 45 years old male, 180 cm tall. I did the mini gastric bypass on 17/3/2010 - I was 126 kgs. To date I have lost around 55…
- You can ask a local bariatric practice for a free insurance check or cost quote
- You should schedule a phone or in-person consultation (both often free), if you are interested in learning more about weight loss surgery
Despite its impressive results, mini gastric bypass is not performed by nearly as many surgeons as some of the more popular procedures. As a result, if you are interested in MGBP but can’t find a surgeon near you, you may need to consider traveling for surgery.
Use the directory below to find the closest mini gastric bypass surgeon.