Gastric Sleeve Diet: Pre-op and post-op Guidelines

Gastric sleeve surgery is a safe and clinically proven method for reducing body weight. The procedure involves decreasing stomach size by separating the upper part of the stomach, called the fundus, from the rest of the organ. A smaller stomach means a smaller appetite. You get full quicker and are therefore less likely to overeat. 

The effectiveness of gastric sleeve surgery depends a great deal on your pre-op and post-op diet. Below are some guidelines on maximizing the gains from a leading weight-loss procedure.

What Is a Gastric Sleeve?

The gastric sleeve is the functional part of the stomach after gastric sleeve surgery, also called a gastrectomy. It represents about 15% of the stomach’s original volume. The sleeve is separated from the rest of the organ, which plays no further role in the body’s digestive process. Its small size reduces appetite and aids in long-term weight control. Gastric sleeve surgery is permanent – it cannot be reversed.

What Should I Eat Before Gastric Sleeve Surgery?

The pre-op diet is your food-consumption plan for the period leading up to your gastric sleeve procedure. Your diet is critical to the surgery’s success for three reasons:

• It makes the procedure safer and easier. The pre-op diet helps reduce fatty deposits around the liver, which improves surgical access to the stomach.
• It lowers the risk of complications. Obesity increases the risk of medical complications during and after surgery; weight loss can counteract that risk. 

• It starts you on the habits you’ll need to make a lifelong commitment to weight control. You’ll gain the confidence that comes with settings goals and achieving them.

In many cases, you should begin your pre-op diet for a gastric sleeve surgery three weeks before your procedure. Please talk to your program dietician or coordinator for more details on when to begin your diet. 

Pre-Op Gastric Sleeve Diet: 3 Weeks Before Surgery

In the three weeks prior to surgery, you will usually plan your meals to:

• Reduce calories – especially carbohydrates. Carbohydrates are a major contributor of calories to most American diets. Refined sugars, like those in candy and soft drinks, should be eliminated. Other sources of carbohydrates, like breads and pasta, are not bad in and of themselves, but limiting their intake can have a positive effect on your weight. 
• Maximize protein intake. Eat 60 or more grams of protein daily. Good sources of protein include chicken, lean ground beef, eggs, and salmon. 
• Focus on healthy fats. It’s a myth that all fats are bad for you. Some are, some aren’t. Healthy fats are found in foods like fish, nuts, and olives. Other fats, like those found in butter or oils, should be curtailed. Trans fats should be avoided altogether. 
• Don’t dehydrate. Drink plenty of water in the weeks before your procedure. Reduce or avoid soft drinks and alcoholic beverages. 

Many programs recommend eating 800 to 1,200 calories a day and sticking with these guidelines until two or three days before your gastric sleeve surgery procedure. Please check with your program coordinator or dietician for more details. 

Pre-Op Gastric Sleeve Diet: 2-3 Days Before Surgery

Two or three days before surgery you’ll need to switch to an all-liquid diet. Restrict your food intake to water, broth, gelatins, and low-calorie sports drinks (no sodas). You’ll need to cut out consumption entirely starting at midnight on the day of your surgery – even water. Failure to follow these guidelines may jeopardize your eligibility for the gastric sleeve procedure.

What About My Medications?

Certain medications must also be discontinued prior to surgery. Included are:

• Arthritis medications
• NSAIDs, including aspirin and aspirin alternatives, such as Tylenol, Advil, Motrin, and Aleve
• Herbal supplements
• Anticoagulant (blood-thinning) medications

Be sure to ask your doctor for more details and if you have concerns about medication restrictions prior to surgery. 

What is the Post-Op Diet for Gastric Sleeve?

Your post-op diet – what you eat in the weeks and months after your gastric sleeve surgery – is just as important as your pre-op diet. You will begin with liquids and then gradually reintroduce solid foods.

Following your post-op diet is essential if you want to realize the benefits of a bariatric procedure. It will also help you avoid potential health complications, including diarrhea, nausea, vomiting, constipation, and gastric leaks. Here is a week-by-week diet plan detailing what to eat after a gastric sleeve surgery:

Post-Op Gastric Sleeve Diet: 1st Week After Surgery

During your first week after surgery, you will be restricted to clear liquids. In addition to water, you can drink clear broth, decaffeinated beverages, and the sugar-free versions of drink mixes like Kool-Aid and Crystal Light. Forgo carbonated beverages, caffeine, and anything with added sugar.

Post-Op Gastric Sleeve Diet: 2nd Week After Surgery 

The second week will see the addition of thicker liquids to your post-op diet. These might include such items as applesauce, cream of wheat, Greek yogurt, protein shakes, and sugar-free ice creams and puddings. 

Post-Op Gastric Sleeve Diet: 3rd Week After Surgery 

Soft and pureed foods come next. Examples include eggs, ground meats, fish, beans, cooked vegetables, and soft fruits. Other possibilities include hummus and cottage cheese. 

Post-Op Gastric Sleeve Diet: 4th Week After Surgery 

Solid foods are finally back in the fourth week after surgery. At this point, the post-op diet is similar to your presurgical diet. Certain items remain off limits: fried foods, candy, nuts, seeds, whole dairy products, breads, pastas, and fibrous vegetables such as broccoli. You are allowed to reintroduce caffeine, but only in small quantities.

Over time, you can add some of the excluded items above but always as small portions. Your focus should remain on lean protein, complex carbohydrates, and healthy fats. Avoid processed foods and sugar-added products. Eat slowly, chew thoroughly, and stop eating when you stop feeling hungry. 

Gastric Sleeve Surgery at Baptist Health

Baptist Health is a leading provider of gastric sleeve surgery and other bariatric care services in Kentucky and Southern Indiana.