How Does the Sleeve work?

Find out how much weight you can expect to lose after gastric sleeve surgery

While it is impossible to predict the precise amount of weight that you will personally lose following surgery, research studies involving thousands of patients have provided us with a pretty good sense of what an AVERAGE patient can typically expect to lose.

Weight Loss Calculator

What is your gender?*


  • Current Weight
  • BMI
  • Weight Class

Your *estimated weight loss and new weight 18 to 24 months following surgery is:

  • Your estimated weight loss*
  • *Estimated new weight

Average Weight Lost
Upper Range Weight Lost
Lower Range Weight Lost


60% of excess body weight lost

Upper range

70% of excess body weight lost

Lower range

50% of excess body weight lost

*DISCLAIMER: Weight loss results can vary depending on the individual. There is no guarantee of specific results. Whether genetic or environmental, it should be noted that food intake, rates of metabolism and levels of exercise and physical exertion vary across individuals. This means weight loss results will also vary from person to person.

Find out if gastric sleeve surgery is the best option for you.

You do not qualify for Gastric Sleeve surgery based on your current BMI and body type.

Your weight exceeds the limit for private, out-of-hospital surgery. Please speak with your family doctor for a referral to the Ontario Bariatric Network.

Weight loss surgery is about more than losing weight!

It dramatically improves many other health issues – literally from head to toe – for better overall health, wellness and quality of life.



57% resolved


55% resolved

Pseudotumor Cerebri

96% resolved


82% improved or resolved


82% risk reduced


52% – 92% risk reduced

High Blood

42% – 66% resolved

Stress Urinary

44% – 88% resolved

Osteoarthritis /
joint disease

41% – 76% resolved

Obstructive Sleep Apnea

74% – 98% resolved


63% resolved

Fatty Liver

90% improved steatosis
37% reduction of inflammation
27% reduction of fibrosis

Metabolic Syndrome

80% resolution

Type 2 Diabetes

83% resolved


79% resolution of hirsutism
100% resolution of dysfunction

Venous Stasis Disease

95% resolved


89% reduction in 5-year mortality

Quality of life

Improved in 95% of patients

Ready to take your first step towards permanent weight loss?

The most critical decision you make is choosing the right surgeon and aftercare program.

Contact Us


  • How much time do I need to take off of work?

    Most patients are back to their “normal selves” in about a week or less (similar to gallbladder surgery). However, if possible, we suggest patients take 2-4 weeks off from work to focus on adjusting to their new stomach and lifestyle.

  • Will I have scars after the surgery?

    The surgery is performed laparoscopically and typically involves 5 tiny incisions. 4 of these incisions are about 5mm (the width of a pea). One of the incisions is approximately 15mm (less than the width of a loonie ).

  • How long will I be in hospital?

    Patients are monitored for about 24 hours after surgery.

  • Will I be completely asleep during the procedure?

    Yes. An expert, board-certified anesthesiologist will be present to ensure you are completely asleep for the entire duration of the procedure.

  • How long does the actual operation take to perform?

    For most patients, once they are asleep, the procedure takes less than 30min to complete.

  • Do I need to take vitamins after the surgery?

    Yes. You will need to take a few daily vitamins for the rest of your life to ensure that you are as healthy as possible.

  • Is the surgery reversible?

    Since we remove the stretchy portion of the stomach, this procedure cannot be reversed. In unusual circumstances, we can convert it to a gastric bypass or a duodenal switch, but this is rarely necessary. Read on for more information.

  • Will I be able to dine at restaurants with family and friends?

    Dining out is often the focal point of many social events. This habit won’t change much after you have weight loss surgery, but your portion sizes definitely will. Whether you are going to a big chain restaurant or stopping at a convenience store for a snack, eating out after bariatric surgery is certainly possible as long as you continue to focus on making healthy choices to ensure that you are meeting your daily protein goal. Remember, now that you’ve had bariatric surgery, it may be helpful to try to share a meal with a friend, ask for a box ahead of time, or order off the kids menu to help you to watch portion sizes.

  • Will weight loss surgery also improve my other medical conditions?

    Weight loss surgery will often completely cure or significantly improve virtually every obesity-related disease. This includes: high blood pressure, Type 2 diabetes, high cholesterol, sleep apnea, coronary artery disease, infertility, polycystic ovarian syndrome, osteoarthritis, and urinary stress incontinence to name a few!

  • Is this procedure like a “lap band”?

    No. This procedure is quite different from a lap-band. It does not involve placing any foreign materials into your body. The gastric sleeve results in numerous hormonal and biochemical changes within your body to help curb your appetite and keep your body from storing fat. The gastric sleeve has become the most commonly performed procedure in North America and has essentially replaced the old lap-band procedure.

Our Clinic Update

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