Gastric Sleeve Diet

“You need to diet for two weeks before surgery,” the doctor says. He looks serious, and he tells the patient to take him seriously when it comes to the gastric sleeve diet. Unfortunately, too many patients, the pre- and post-surgery diets feel like unnecessary formalities—the patients just do not see the point.

To be fair, studies proving that pre-bariatric surgery diets are actually significant are quite recent. It is very possible that a patient seeking gastric sleeve surgery may know of someone who was not asked to diet as rigorously prior to the surgery.

However, as more and more studies emerge, it becomes clear: pre- and post- operative dieting is crucial to the safety and success of gastric sleeve surgery. This surgery already is the safest of the main bariatric surgeries—it is important to give it the highest chance of success possible.


Why Diet Before Bariatric Surgery?

Currently, most gastric sleeve surgery is done laparoscopically. Laparoscopic surgery is when, instead of a single, long, incision, the surgeon only makes a few, around 4 to 6, small incisions in the stomach. A camera is used so that the surgeon can navigate the procedure through only those small incisions. The area heals faster, the body is less traumatized, and the procedure is safer overall.

Laparoscopic surgery is possible when the liver can easily be lifted out of the way so that the stomach can be operated on. The heavier and harder the liver, the more difficult it is for the surgeon to lift the liver out of the way. If it cannot be moved, the surgeon may either opt to use open surgery—one large incision—or to forbid surgery until the diet is followed.

Especially in obese patients, the liver is large because there are fatty cells among the liver cells. The way to soften the liver and reduce its weight is by going on a diet that limits the glycogen (the sugar stored in muscles and the liver as an energy source) intake. This forces the body to feed on the glycogen already in the liver, softening and shrinking it.

Ease of surgery, however, is not the only reason that a pre-surgery diet is important. Whenever surgery is performed, it always and inevitably causes surgical trauma in the patient. No matter how clean the surgery or how healthy the patient, the body reacts to the invasive experience through inflammation at the area, and interruption of the normal fat hormone synthesis of the body. However, the healthier the patient and the less the fat that needs to be cut through, the less is the surgical trauma. This gives the patient a better chance of success and recovery.

In other words, by following a pre-surgery diet, two proverbial birds are killed by the proverbial stone: the surgery becomes easier and therefore safer for the surgeon, and the patient becomes better able to receive the surgery.

Pre-Surgery Gastric Sleeve Diet

The pre-surgery diet is usually ordered to begin at least 2 weeks before the surgery date. This ensures that the patient loses enough liver weight and is in better health and shape to actually go through the surgery. The basic guidelines of a pre-surgery diet are as follows.

Increase protein intake. Basically, protein is the body’s maintenance mechanism. It repairs and builds needed parts of the body, such as muscles and organs. Also, protein keeps the dieting body from eating muscles when it starts to find internal energy sources. That way, the body only attacks the fat, and leaves the muscles alone. Protein may be found in foods like lean meat. Protein-rich foods also make it easier to diet because they tend to be very satisfying, and the patient does not get hungry too quickly. As the body digests the protein, more calories burn in the process because protein is harder to digest.

Decrease carbohydrate intake. Carbohydrates are the main energy source of the body. When digested, they are broken down into glucose, or blood sugar, which is then burned by the body to get energy. If there is too much glucose, the body puts it away in the muscles and liver to burn when needed. If less carbohydrates are going into the body, the body is forced to burn the glucose it already has. This reduces liver size and overall fat content. Foods rich in carbohydrate are breads and cereals, whole grain; and vegetables rich in starch (i.e. potatoes). Processed foods with sugar added as preservative also are considered rich in carbohydrates.

Stop eating and drinking non-natural sugars. Sugar can be naturally found in fruits and honey, but should still be taken in moderation. In the 2-week pre-surgery diet, it is better to reduce intake of those as well. However, what should definitely be avoided is the sugar found in sodas, candies, fruit juices (both mixed and pure), and baked sweets such as cookies and cake. Since sugar is a carbohydrate, the body breaks it down into glucose and stores whatever is not burned as fat. Completely stopping the intake of non-natural sugars will force the body to burn the existing stores of fat.

The 2-week diet can look roughly like this:

  • Sugar-free protein shakes. Protein shakes have controlled protein content, and are easy to digest. They are also handy if the patient still goes to work regularly.
  • A small amount of grain with added lean meat or other protein source. The 1 slice of bread may be eaten with a small amount of cereal or other kind of grain. The added protein sources include eggs, chicken, other lean meats, and cheese. This should all be eaten with a salad of vegetables and fruits, with no or extremely low-fat dressing.
  • Snacks of small protein-rich foods. Usually, the patient gets hungry in between lunch and dinner. If that is the case, 1 small, fruits-and-nuts energy bar should be enough.
  • Low-sugar fluids. If possible, drink only water. Milk, fruit juices, tea, and coffee are all permissible.

It looks difficult, but the help that it gives to both surgeon and patient is immeasurable.

Why Diet After Bariatric Surgery?

If the pre-surgery diet is designed to make surgery safer for both surgeon and patient, the post-surgery diet is designed to continue the success. Before the surgery, the aim was to lower the liver size and the risk of surgical trauma. With the post-surgery diet, the aim is to promote healing and recovery. A well-designed, strictly followed diet also lessens the risk that the patient will go back to his old eating habits after the surgery.

There are other motivations besides these abstract ones. After all, the patients cannot literally see the proteins healing the body, so they might ignore the diet because the results, they think, cannot really be known. However, fact: bariatric surgery, gastric sleeve surgery included, has some very uncomfortable results after surgery. These include diarrhea or constipation, dehydration, or gastric leak, if the diet is not followed properly.

The body is reacting to the new situation, and needs a few weeks to get back on course. Now, while the surgeon can refuse to operate unless the pre-surgery diet is followed, the post-surgery diet is the responsibility of the patient. He can follow or not follow it. All the surgeon can do is fix whatever goes wrong if there is a post-surgery issue because of an unfollowed diet.

It is best for the patient to plan for the post-surgery diet even before the surgery. The pre-surgery diet helps to get the patient into the habit of dieting. However, the patient makes it much easier on himself if he has friends or a support group who know his diet, and are supportive and stern when need be.

Gastric Sleeve Post-Surgery Diet

After gastric sleeve surgery, the first thing the patient has to get used to is not feeling hungry, but having the habit of eating. After most of the stomach is removed in gastric sleeve surgery, the stomach produces much, much less of ghrelin, the hormone that signals your body to eat because it is hungry. In other words, the patient will literally not have the desire to eat, but the mental habit of eating will remain. That makes for a lot of post-surgical confusion.

Several general guidelines apply. First, the patient should eat 3 meals a day without fail—but no more than 3. He should have set breakfast, lunch, and dinner times, and stick to them. The regularity makes it easier to lose weight and avoid gaining it, by eating as few snacks as possible. Second, the patient should chew (when applicable) the food very carefully. It lowers calorie intake and makes it easier for the stomach to digest.

Third, when the patient feels full, he should stop eating. If he forces himself to continue, the stomach may stretch and the surgery will be useless. Last, the patient should not drink fluids before, after, and during meals. There should be half-an-hour’s wait time before and after the meal, so that the stomach won’t be stretched, and the “full” feeling will last longer.

The post-surgery diet for gastric sleeve takes place over 4 to 5 weeks. Each week introduces another level of eating back into the diet.

Week 1: clear liquids. The newly-shrunk stomach should not be given too much work to do, and the staples holding the stomach together should not be strained. Clear liquids are cleansing to the body, and easily taken in and passed through the recovering digestive system. They include water (as much as possible); broth; tea and coffee without caffeine, sugar, or any other additions; Jell-O, non-carbonated drinks, and popsicles, all sugar-free. Rather than using a straw or drinking straight out of a bottle, the patient should sip slowly from a wide-rimmed mug or glass. This lessens the discomfort of air bubbles in the stomach.


Week 2: liquid proteins. Before the surgery, protein was important because it held muscles while allowing fat to burn. After surgery, protein rebuilds the parts of the body damaged during surgery—in other words, it heals them. After a clear liquid diet, the patient should transition to liquids that are high in protein. These include clear liquids mixed with protein powders, non-fat yogurt, watery oatmeal, thin creamy soups, soft-noodle soup, and other watery foods high in protein.

Week 3: pureed food. By week 3, there are two goals: first, re-introduce the stomach to the taste of regular food. Second, know which foods cause the most discomfort. The foods should still be low in fats and sugars, and high in protein. These include cereals left sitting in milk (non-fat) until soft; vegetables boiled or steamed soft; scrambled eggs; soups; and protein shakes. After each new food that is introduced, the patient should study his body’s reaction. If he has diarrhea, constipation, or other negative reactions, he should wait for his body to adjust, or adjust the food.

Week 4: soft but real food. Now that the patient knows which foods do not cause too much discomfort, he can start the transition to other, more normal foods. These include chicken and beef, cooked until tender, and chewed very thoroughly; fish, any kind; cereal, can now be eaten crunchy; potatoes, mashed or baked soft; and fruits and vegetables. Because some of these are also new foods, the patient should still observe his body’s reactions to the food.

On no account should foods such as french fries and other fried foods, candy, cakes and cookies, pasta and pizza, and whole-milk dairy products. Carbonated and sugary drinks should also be avoided at all costs.

Week 5: real food. After week 4, the patient can now start eating more “real food.” He should still test each food, to make sure that his bodily reactions are not negative. Since he can eat less, he should target nutrient-rich foods, or foods that are more dense in vitamins and minerals than others, such as fruits, lean meats, and other kinds. This diet should be kept lifelong for the best results.


The Gastric Sleeve Diet: Not Just A Formality

Surgeons and physicians are not just being dramatic when they require extensive dieting. Pre-surgery dieting is one of the best ways to ensure the patient’s safety during the surgery and his recovery. Post-surgery dieting is the only way that the patience can make sure his surgery works. For the results that are seen before and after gastric sleeve surgery, this change of lifestyle is absolutely necessary.