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Khalili Center’s Gastric Bypass Aftercare Recovery Program.

Our connection with our patients does not end after completing a procedure. Our comprehensive support program can assist you in your journey to recovery.

The aftercare program consists of monthly walks with the doctors, consultations with a dietitian, psychological counselor sessions, community activities, and health information support.

We have helped our clients recover and live a more meaningful and active lifestyle after their surgery.

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A Leader in Gastric Bypass Surgery in California

The Khalili Center founder, Dr. Theodore M. Khalili, is a board-certified surgeon who has performed over 8,000 bariatric surgeries, including gastric bypass, Lap-Band, and gastric sleeve surgery. He had also performed the first robotic-assisted bypass surgery in the United States in 2002.

Dr. Khalili is a board-certified member of the American Society for Metabolic and Bariatric Surgery (ASMBS). He is also a member of the American College of Surgeons, American Medical Association, and American Society of Bariatric Surgery.

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My name is Dr. Theodore Khalili, surgeon and founder of Weight Loss Surgery of Southern California. I founded the Center because I have dedicated my life-long professional work to patient care. My approach to patient-centric partnerships and service-oriented facilities offer a comprehensive and holistic approach to bariatric treatment – all in one place.

I believe that patient care does not end right after surgery – it’s only the beginning. I founded the Center to give patients access to a supportive community that guides them through each step of the weight loss journey. We work with a team of registered dieticians, psychologists and general doctors to create tailored, best-in-class care available.

I have performed over 8,000 bariatric surgeries…

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Dr. Theodore M. Khalili,
Founder and Director
Khalili Center for Bariatric Care


Gastric bypass is a laparoscopic surgery wherein the surgeon performs the procedure through small incisions on the abdomen. The surgical procedure is a minimally-invasive approach compared to open surgeries with large incisions.

Once you have booked your surgery with our bariatric doctors, we will turn you over to our patient care program to assist you in pre-surgery preparation.

Our dietitian may provide a diet plan a few weeks before the surgery. The diet plan may include a few foods and drink restrictions. You may also be advised to follow an exercise routine to prepare for the surgery.

Pre-surgery diet and exercise might reduce liver volume, reducing the risk of surgery complications(1).

Experts also advise that weight loss before surgery may influence the success of the procedure(2). Moreover, it has been observed that lifestyle changes and weight loss before the operation resulted in a shorter hospital stay(3).

You may need to make arrangements to have someone help you with your daily tasks after surgery, such as house chores, taking care of the kids, and running errands.

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How Long Is the Recovery Period?

The laparoscopic gastric bypass surgery has faster recovery times and shorter hospital stays compared to open surgeries. You may be discharged two to three days after your operation.

A comparison has been documented showing that patients who underwent laparoscopic gastric bypass surgeries stayed in the hospital for 2.5 days, while open surgery patients stayed for 3.5 days(4).

The recovery period varies per patient. In most cases, patients can gradually go back to work around three weeks after the surgery. The first follow-up appointment is typically around six weeks after surgery(5).

Post-op Notes: What to Expect

in Diet

Post-op guidelines include food restrictions for one to two days to let your stomach and small intestine heal. On the third day, our dietician will provide a diet plan composed of a liquid diet for the next few weeks before transitioning to soft foods.

Experts acknowledge that the post-surgery liquid diet is the first step to the nutritional progression protocol that can encourage you to make healthy choices and less food intake(6).

Once you have been cleared for solid food intake, you must take small meals for the rest of your life or until the surgery has been reversed.

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Pain Medication and

Your bariatric surgeon will prescribe pain medication for the first week of recovery to help you feel comfortable.

However, note that some pain medicines may cause side effects. It is well-documented that patients who have had weight-loss surgeries are more susceptible to gastric ulcers caused by pain medication(7).

To avoid complications, take pain medications prescribed to you only by our bariatric surgeon.

Our dietician will also advise you to take mineral supplements, such as vitamin B12, calcium, and multivitamins, to make up for the nutrient shortage from your liquid diet.

These supplements are essential as they can prevent loss of nutrition in weight loss surgery patients(8).

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and Work

You may be low in energy during the first week due to low-calorie intake, and you would need assistance.

On the first day after your procedure, you will be encouraged to take a few steps. In the second week or third week, you can start taking short walks.

You will be encouraged to return to work and other normal activities gradually. Avoid driving while you are still on your pain medication.

Do not engage in strenuous activities during the first six weeks. Light activities, like taking a short leisurely walk, are recommended during this time. But once fully recovered, you must develop a regular exercise routine or physical activities for weight loss maintenance.

A review posted by Diabetes, Obesity, and Metabolism journal mentioned that engaging in physical activities after bariatric surgeries contributed to metabolic improvements(9).

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Guides and Tips for Faster Healing

The Khalili Center will provide support while you make the necessary lifestyle changes. Here are our tips on how you can heal faster and start living the life you deserve:

  • Avoid solid foods for the first few weeks and gradually change to pureed foods in the following weeks. Once you are used to your new stomach, take small amounts of solid food upon our dietician’s advice.
  • Once you are fully recovered, you must maintain a healthy diet composed of leafy greens, lean meats, and clear liquids. Better eating habits can help in providing long-term success in your weight loss journey.
  • Opt for small meals and soft food as much as you can.
  • Keep a regular exercise regime. An active lifestyle can reduce excess weight.
  • Consult your bariatric surgeon before taking pain medication. Generally, gastric bypass patients have a higher risk of developing stomach ulcers with non-steroidal anti-inflammatory drugs (NSAIDs)(10).
  • Avoid caffeine and alcohol. Regular water intake is essential.
  • Join a support group to hear the experiences of other patients and build healthy relationships.
  • Allow your body to heal by taking significant time off work.

Why Choose the Khalili Center for Gastric Bypass Surgery.

A pioneer in minimally-invasive bariatric procedures, Dr. Khalili, possesses an unbeatable track record that resulted in countless long-term success stories among patients with medical conditions, such as obesity and diabetes.

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Dr. Khalili is also considered as one of the most influential educators in the industry. In 2005, he won the Golden Apple Award as an outstanding educator.

He has trained many surgeons in minimally-invasive weight loss procedures. His students have become successful bariatric surgeons in weight loss surgery programs all over the world.

The Khalili Center is also at the forefront of bariatric innovation. Dr. Khalili and his doctors have contributed several papers and research on laparoscopic procedures and bariatric surgeries. Their research has been a well-known authority in bariatric surgery, general surgery, minimally-invasive techniques, and robotics. Click here to read more about our doctors and their credentials, and find out how they can help you best.

Understanding Gastric Bypass Surgery

Gastric bypass surgery is a bariatric (weight loss) procedure that involves major adjustments in your digestive system. Also known as a roux-en-y gastric bypass, this procedure lets food bypass some parts of the stomach and small intestines.

Like other bariatric surgeries, such as sleeve gastrectomy and Lap-Band, gastric bypass surgery can significantly treat obesity and related health conditions.

A gastric bypass surgery’s result leads to fewer absorption of calories and significant weight loss. The International Federation for the Surgery of Obesity 2018 global registry report shared that 394,431 gastric bypass operations had been performed worldwide(11).

Gastric bypass surgery is exclusive to patients who have reached a body mass index (BMI) of 40 or more. The inability to achieve weight loss is also a qualifying factor for the surgery(12).

How Gastric Bypass Works

The procedure is usually performed laparoscopically. This technique creates small incisions on your abdomen. Narrow tubes are inserted into the incision sites to allow the surgeon to insert a small camera (laparoscope) and surgical instruments. The procedure is viewed via a monitor. 

A gastric bypass procedure is conducted by creating a small stomach pouch and then rerouting it directly into the small intestines. A stapling method separates the small pouch from the rest of the stomach.

When you take your next meal two days after the surgery, you will feel full more quickly with your smaller stomach. The lesser amount of food intake eventually leads to significant weight loss.

Expected Results of Gastric Bypass Surgery

Gastric bypass surgery has been scientifically proven to improve the quality of life of individuals suffering from obesity. The procedure has significantly reduced body weight, lowered heart disease incidence, and diabetes symptoms(13).

A gastric bypass procedure is often done laparoscopically. Compared to open surgeries, the procedure is minimally invasive and has a faster recovery time. The one-centimeter scars are less painful and require less maintenance compared to larger incisions. 

It is well-documented that the surgery’s long-term effects make the risks and recovery period worth it(14).

Generally, patients who undergo gastric bypass surgery experience a 9% weight loss in the first year. Sixth-year follow-ups have shown that patients had a 34.9% reduction of their initial weight (15).

Besides weight loss, gastric bypass surgery has been known to improve self-esteem and reduce depression and anxiety in patients(16)

More importantly, the procedure reduces risks and symptoms of the following medical conditions (17):

  • High blood pressure
  • Sleep apnea
  • Type 2 Diabetes
  • Heart disease
  • Acid reflux
  • Fatty liver disease
  • Joint pain
Possible Side Effects of a Gastric Bypass Surgery

Like any weight loss surgery, gastric bypass surgery comes with risks and side effects. During the consultation, our doctors will make sure you are well-informed before deciding how you want to proceed. 

You will be guided by our doctors accordingly to avoid the risks of side effects, which include the following(18):

  • Infection
  • Bowel obstruction
  • Abdominal pain
  • Blood clots
  • Dumping syndrome (flushing, diarrhea, nausea, lightheadedness)
  • Hernias
  • Gallstones
  • Low blood sugar (hypoglycemia)
  • Ulcers
  • Malnutrition
  • Acid reflux
  • Vomiting
  • The need for a follow-up or correction surgery
  • Death (rare)


  1. Sherf Dagan, S., Goldenshluger, A., Globus, I., Schweiger, C., Kessler, Y., Kowen Sandbank, G., Ben-Porat, T., & Sinai, T. (2017). Nutritional Recommendations for Adult Bariatric Surgery Patients: Clinical Practice. Advances in nutrition (Bethesda, Md.), 8(2), 382–394. https://doi.org/10.3945/an.116.014258
  2. Sun Y, Liu B, Smith JK, et al. Association of Preoperative Body Weight and Weight Loss With Risk of Death After Bariatric Surgery. JAMA Netw Open. 2020;3(5):e204803. doi:10.1001/jamanetworkopen.2020.4803
  3. Roman M, Monaghan A, Serraino GF, et al. Meta-analysis of the influence of lifestyle changes for preoperative weight loss on surgical outcomes. Br J Surg. 2019;106(3):181-189. doi:10.1002/bjs.11001
  4. Fisher BL. Comparison of recovery time after open and laparoscopic gastric bypass and laparoscopic adjustable banding. Obes Surg. 2004;14(1):67-72. doi:10.1381/096089204772787310
  5. National Institute of Health. Gastric Bypass Recovery. https://www.nbt.nhs.uk/our-services/a-z-services/bristol-weight-management-bariatric-service-bwmbs/bristol-bariatric-6
  6. ANDRADE, Camila Garcia da Costa, & LOBO, Amanda. (2014). Weight loss in the first month post-gastroplasty following diet progression with introduction of solid food three weeks after surgery. ABCD. Arquivos Brasileiros de Cirurgia Digestiva (São Paulo), 27(Suppl. 1), 13-16. https://doi.org/10.1590/s0102-6720201400s100004
  7. Scheffel, O., Daskalakis, M., & Weiner, R. A. (2011). Two important criteria for reducing the risk of postoperative ulcers at the gastrojejunostomy site after gastric bypass: patient compliance and type of gastric bypass. Obesity Facts, 4 Suppl 1(Suppl 1), 39–41. https://doi.org/10.1159/000327340
  8. Sherf Dagan, S., Goldenshluger, A., Globus, I., Schweiger, C., Kessler, Y., Kowen Sandbank, G., Ben-Porat, T., & Sinai, T. (2017). Nutritional Recommendations for Adult Bariatric Surgery Patients: Clinical Practice. Advances in nutrition (Bethesda, Md.), 8(2), 382–394. https://doi.org/10.3945/an.116.014258
  9. Coen, P. M., & Goodpaster, B. H. (2016). A role for exercise after bariatric surgery?. Diabetes, obesity & metabolism, 18(1), 16–23. https://doi.org/10.1111/dom.12545


  1. Scheffel, O., Daskalakis, M., & Weiner, R. A. (2011). Two important criteria for reducing the risk of postoperative ulcers at the gastrojejunostomy site after gastric bypass: patient compliance and type of gastric bypass. Obesity Facts, 4 Suppl 1(Suppl 1), 39–41. https://doi.org/10.1159/000327340
  2. International Federation for the Surgery of Obesity 2018 global registry report. Retrieved from https://www.ifso.com/pdf/4th-ifso-global-registry-report-last-2018.pdf
  3. American Society of Metabolic and Bariatric Surgery. Bariatric Surgery Candidate. Retrieved from https://asmbs.org/patients/who-is-a-candidate-for-bariatric-surgery
  4. Adams, T. D., Davidson, L. E., Litwin, S. E., Kolotkin, R. L., LaMonte, M. J., Pendleton, R. C., Strong, M. B., Vinik, R., Wanner, N. A., Hopkins, P. N., Gress, R. E., Walker, J. M., Cloward, T. V., Nuttall, R. T., Hammoud, A., Greenwood, J. L., Crosby, R. D., McKinlay, R., Simper, S. C., Smith, S. C., … Hunt, S. C. (2012). Health benefits of gastric bypass surgery after 6 years. JAMA, 308(11), 1122–1131. https://doi.org/10.1001/2012.jama.11164
  5. Courcoulas, A. P., Yanovski, S. Z., Bonds, D., Eggerman, T. L., Horlick, M., Staten, M. A., & Arterburn, D. E. (2014). Long-term outcomes of bariatric surgery: a National Institutes of Health symposium. JAMA Surgery, 149(12), 1323–1329. https://doi.org/10.1001/jamasurg.2014.2440
  6. Madura, J. A., 2nd, & Dibaise, J. K. (2012). Quick fix or long-term cure? Pros and cons of bariatric surgery. F1000 medicine reports, 4, 19. https://doi.org/10.3410/M4-19
  7. Susmallian, S., Nikiforova, I., Azoulai, S., & Barnea, R. (2019). Outcomes of bariatric surgery in patients with depression disorders. PloS one, 14(8), e0221576. https://doi.org/10.1371/journal.pone.0221576
  8. The Mayo Clinic. Gastric Bypass Surgery Overview. Retrieved from https://www.mayoclinic.org/tests-procedures/bariatric-surgery/about/pac-20394258#:~:text=After%20bariatric%20surgery,diet%20for%20a%20few%20weeks.
  9. Ibid

Your Journey to Overcoming Obesity Starts Here.

Weight loss surgery is a tool to reset your life.

Our comprehensive program is everything you need to set you up for your new life and to keep the weight off. All you have to to find out if we’re right for you is to book an appointment.