How Bariatric Surgery Works: The Bypass


So, this is the third in my series reviewing the three main surgeries we do for weight loss.  The one I want to talk about today is the gastric bypass.  Many people have heard of it but it is also surrounded by many misconceptions.  My intention with this email is to give a brief explanation of how it works and how it is different from the band and the sleeve.  First off, it is the one that generally leads to the greatest amount of weight loss and if you are a diabetic it is the most effective in improving and in many cases resolving Type II diabetes!

Dr. Michael BilofDr. Michael BilofQuick review, my two previous emails discussed the Band
and the Sleeve.  If you recall, the band works simply by restricting how much food a person can eat..picture an hourglass.  The sleeve works also by restricting the amount of food a person can eat, but in addition has a "chemical/hormonal" effect.  We discussed how this decreases a persons appetite for a long period of many cases for several years.  This decrease in appetite obviously helps patients lose weight as it is much easier to limit your intake of calories if you are not hungry. If you would like to read the full write-ups of the two procedures the description of the band is here:


and the sleeve is here:


So, now lets talk about the gastric bypass.   The bypass is a fairly complicated operation and  this is obviously a brief overview, but I hope to gives you an idea of how it works.  The bypass basically does four things to help a patient lose weight, it does what the band and the sleeve do plus some additional things.   


First, it gives a patient restriction (like both the band and the sleeve) reducing the size of the stomach from about 32 ounces (a quart) to about 2 ounces (roughly the size of an egg).  Secondly it also has the same "chemical/hormonal" effect as the sleeve, which means it shuts off a person's appetite after the surgery.  As I mentioned last time the reduction in appetite is not permanent although it will last for quite a long period of time…for many patients as long as several years.  


The other two ways this surgery works involves the "bypass" part of the bypass.  With a gastric bypass we actually re-arrange part of the intestines so the food you eat after this surgery "bypasses" part of the stomach and part of the intestines.  This means the food will not be absorbed into the bloodstream as efficiently after the surgery as before.  The technical term for this is "malabsorption".  What this means is that your body won't be absorbing fats and sugars into your bloodstream as quickly and this helps you lose more weight.  We believe this is why the bypass is better for diabetics. Since we are bypassing the first part of the intestines and decreasing the absorption of sugars the surgery helps resolve patients diabetes at much higher rates than both the band and the sleeve.


There is one other thing that happens with this "re-arrangement" of the is called "dumping syndrome".  If you know anyone who has had a gastric bypass or if you have done any research about it you may have come across this term.  Basically what it means is that if someone eats sugary foods after this surgery (cakes, cookies, ice cream etc) that you get sick (nausea, cramping diarrhea etc…sort of like how you might feel if you got a GI virus).  


So, we can see that the bypass has four different ways in which it works to help patients lose weight: 1) Restriction 2) Malabsorption 3) Dumping Syndrome 4) Decreased appetite.


Obviously this was a quick review of a complex surgery, but I hope it gives you a sense of how it is different from both the band and the sleeve.


Support Group:


Going forward we are going to have one support group per month.  The summer schedule is as follows:

Wednesday July 13th: Plastic Surgery Options after Weight Loss Surgery

Wednesday: August 10th:  Nutrition Topic: Eating on the Run and Dining Out Tips

All sessions will be held at the Ambulatory Care Center, 200 South Orange Ave, Livingston, NJ from 6:00 PM until 7:30 PM  


Patient Information Seminar:


If you know anyone who would like to find out more information about all the different options for weight loss surgery we have an information seminar currently scheduled.for tomorrow June 22nd.  It will be at our Millburn office, 225 Millburn Ave, Suite 204, Millburn, NJ starting at 6:30 PM.

If you ever have any question about informational seminars please don't hesitate to call the office or email us at: or to find out when we are having a seminar.  


End Quote:


I have talked to literally thousands of patients thinking of doing this surgery and I know how scary it can seem, with that background here is today's quote:


"The secret of happiness is freedom. The secret of freedom is courage"



Michael Bilof



Contact Information
Web address:
phone: (973) 218-1990

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