What is the Gastric Bypass Diet

The gastric bypass diet is what people must go on for the rest of their lives after they have a gastric bypass. A gastric bypass is a surgery that reduces the size of the stomach using one of a few methods. This reduced, sized stomach is then bypassed or reconnected to the small intestine. A gastric bypass will give significant weight loss very quickly by making it almost impossible to over eat. The patient will be less hungry and require small meals more frequently.

After a person has the gastric bypass surgery their smaller stomach will have a greatly reduced volume. It will go from holding about a quart of contents to just an ounce, or roughly two tablespoons. After some time the stomach will stretch to hold from four to eight ounces, or roughly a half to a full cup, at once. The opening from the small intestine to the stomach will also be reduced to about a fourth of an inch wide. This will slow down the rate that the food can be emptied through the stomach and into the intestine.

How the Gastric Bypass Diet Works

The gastric bypass diet has been created to give you a significant change in weight. You will have to learn all new habits for eating and follow the diet for the rest of your life to maintain the weight loss. Generally speaking, the gastric bypass diet will include those foods that have a larger amount of protein and not a lot of fiber, fat, sugar, or calories. It will be vital that you take mineral and vitamin supplements to maintain your overall health.

Protein is vital because it is what your body needs to build new tissue. If you do not get enough protein after your gastric bypass surgery, your wound will not heal correctly. Protein in your diet will also help you to build muscle which will in turn burn your stored fat more productively. Foods high in sugar such as cookies, candy, ice cream, and pop need to be avoided. You are not allowed a great deal of food at a time, so you'll need to be sure that what little food you can eat will have as much nutritional value as possible. Even in small portions, foods high in sugar and fat can halt your weight loss success. Also, eating them can produce a reaction called dumping. Usually the symptoms of dumping, which include nausea, vomiting, cramping, diarrhea, profuse sweating, and heart palpitations, are enough to keep most people from enjoying sugary foods.

Fatty foods are going to be extremely hard to digest after gastric bypass surgery. If you consume too much fat, you will delay your stomachs ability to empty causing reflux, where stomach acid and food particles back up into your throat giving your severe heartburn. Too much fatty foods can also cause the symptoms of dumping mentioned above. Fiber is generally considered a healthy thing to consume, but if you have had gastric bypass surgery there will not be enough room inside your new small stomach to hold these bulky foods, nor the proper amount of stomach acid to digest them properly. Certain types of fiber can actually become lodged in your stomach and cause a dangerous blocking of the now smaller intestine opening.

Mineral and vitamin supplements are a vital part of any gastric bypass diet. Because the gastric bypass diet will only allow you to consume a small amount of a limited type of foods, you will not be able to get all the minerals and vitamins you need from your diet. You can become severely deficient in certain minerals and vitamins in just a few short months. Some can be life threatening such as potassium, which is vital for the heart to function properly. Some others are foliate, iron, vitamin B12, vitamin D, and calcium.

What Experts Say about the Gastric Bypass Diet

Certain studies are showing that the gastric bypass surgery and diet can be very problematic, especially for young adults, according to Dr. Thomas Inge, the chair of a government study that conducts to see how bariatric surgery affects young adults. The study was established to see if young adulthood is the best time to have this type of surgery. It was started in 2007 and will conclude in 2012.

So far Inge has found that greater than one in five of the participants had a more significant occurrence of a complication called symmetric pouch dilation. This is when the small pouch that is made stretches much larger than planned, allowing the person to consume more food than they should. This is an issue that has also been recorded in the Journal of the American Medical Association, and before that, in the journal of Obesity Surgery. Inge and his team are just waiting on the results from trials in the United States that are independent of the industry to come in to make any final recommendations. Inge and other experts are quick to bring up the fact that studies have so far been few, but those that have been conducted show the gastric bypass surgery to be a safe and effective alternative.

Sample Gastric Bypass Diet Meal Plan


  • ¼ medium banana
  • 1 scrambled egg
  • ½ slice of toast with 1 tsp. margarine

Morning Snack

  • 2 graham crackers
  • ½ cup of sugar-free pudding made with 2% milk


  • 2 oz. broiled chicken breast
  • ¼ cup boiled carrots with 1 tsp. Margarine
  • ½ cup pasta salad

Afternoon Snack

  • ½ cup fruit cocktail


  • 2 oz. baked or broiled haddock
  • ¼ cup green beans
  • ½ dinner roll

Evening Snack

  • 1 oz. American cheese
  • 2 saltine crackers
  • 1 tsp. mustard
Last Updated: Saturday, July 16, 2011