Review the Nutritional Guidelines for Bariatric Surgery Diet

When preparing for bariatric surgery, dietary precautions should be taken before the surgery to get the body in its best shape. This is important to not only facilitate a problem-free procedure but also to help you recover as quickly as possible. Your doctor will probably suggest you lose a certain amount of weight before hospital admission and will tailor nutritional supplementation to your individual needs. 

Changing dietary habits early will make it easier to adapt to your post-surgery diet. Remember that gastric bypass surgery is not only a physical change, it demands a mental alteration in how you think about food and eating. Making the best possible dietary decisions is important for optimal health and maintenance. Positive change is the key to a successful outcome. 

Pre-Bariatric Surgery Diet Guidelines

To help the body prepare for surgery and recovery, dietary choices should revolve around reducing body fat and protecting and preserving muscle tissue. The surgery will be safer and take less time if the entire body, but especially the liver, is not too large or fatty.   

  1. Start using protein powders and shakes. High levels of protein are needed to keep muscle tissue from being used as energy when the body is on a low fat diet. Having a protein shake once or twice a day is an excellent way to get daily requirements without being tempted to overeat. Look for those that are low-sugar and low-carbohydrate.   
  2. Avoid foods that contain fat. Deep-fried foods, fatty meats, deli meats,  and whole milk products like cheese and cream are all off-limits pre-surgery. Stick to small portions of lean cuts of meat and freshly prepared vegetables. 
  3. Avoid sugary foods and drinks. Sodas and candy are not permitted. Staying away from anything that’s overly sugary is always the best policy. Do not think, “Oh, I won’t be able to eat these after the surgery, so I’d better have some now.” That’s a bad idea.    
  4. Stay away from high-carbohydrate foods. Eating foods made with white flour is basically the same as dining on white sugar. The body changes heavy carbohydrates into a form of sugar that does nothing but pack on the pounds. 
  5. Do not smoke or drink alcohol. Activities that restrict veins and blood flow like drinking and smoking are the opposite of what you want to do right before a surgery. Alcohol not only negatively affects the heart and arteries, it causes weight gain. Smoking harms blood vessels and will disturb oxygen flow to recovering organs. 
  6. Avoid using over-the-counter medications. Don’t take things like aspirin, ibuprofen (Advil/Motrin), naproxen (Aleve), and acetaminophen (Tylenol/Excedrin). Ask your doctor for specifics.
  7. Strictly avoid binge eating. Binge eating will make it difficult for your body to expel wastes before your surgery. The last thing you want is for the surgery to carry on longer than it needs to because your body was not prepared in advance.
  8. Stay hydrated.

The primary thing you must remember is that you want your body to be in the best shape it can be to deal with the trauma of surgery and then immediately begin the process of recovery. Don’t make things harder on your body just for immediate gratification. You’ll have a better chance of being successful with your ultimate weight loss goals if you go into surgery prepared.

Post-Bariatric Surgery Guidelines


Because gastric bypass surgery changes your digestion, your post surgery diet will have to accompany those changes. As your stomach heals, you’ll have to be gentle with it. Reintroducing food alone will take time and your tolerance for food products will be different from what it was before the surgery. Starting with clear liquids, you will eventually graduate to puréed foods and then soft foods per your physician’s advice.

Clear Liquid Diet

Keeping well hydrated is most important throughout your surgical journey. It’s a good idea to sip liquids constantly, dilute fruit juices, and avoid extremes of too hot or cold. Remember that while in recovery, it’s common to experience nausea or vomiting.

A few good items to begin with include:

  • Water
  • Fruit juices (apple, grape, or cranberry) Diluted; limit 2 cups daily.
  • Broth (clear beef, chicken, or vegetable)
  • Ice chips
  • Gelatin
  • Popsicles

The clear liquid diet is generally followed for the first one to two weeks post-surgery.

Full Liquid Diet

The full liquid diet is prescribed as a sub-stage after the gastric band surgery, in particular. Patients should continue to ingest 48-64 ounces of clear liquids spread throughout the day and can begin adding the following full liquids at mealtime.

  • Skim milk, with protein powder, added
  • Carnation instant breakfast, no sugar added
  • Meal replacement drinks
  • Yogurt
  • Strained cream soups

Your surgeon will advise as to when to advance to the next stage. 

Pureed Diet

You can begin the pureed diet when your physician gives the okay to move on to foods of thicker consistency. Hydration is still very important and you should continue with your 48 to 64 ounces of clear fluids per day. Stop drinking 30 minutes before mealtime.

Suggested food ideas while on the pureed diet include:

  • Yogurt (plain or sugar-free)
  • Strained cream soups (made with skim milk)
  • Skim milk with 1/2 teaspoon protein powder added
  • Cottage or ricotta cheese (low- or non-fat)
  • Scrambled eggs or egg substitute
  • Mashed white fish or tuna
  • Pureed meats
  • Baby food
  • Cream of wheat
  • Mashed potatoes
  • Applesauce
  • Mashed bananas
  • Pureed fruits (peaches, pears, apricots, pineapples)
  • Tomato juice
  • Pureed vegetables (spinach, green beans, carrots, squash)

It’s a good idea to eat the protein portion of the meal first and don’t forget to have liquids 30 minutes after eating. 

Soft Food Diet   

The soft food diet is stage three of the post gastric surgery diet plan. Your eating habits must change overall to not only promote recovery but to help you to continuously maintain a healthy weight.

A few things to remember for your post-surgery soft food diet include: 

  1. Consume three balanced meals per day. Keep portions small. 
  2. Follow a diet chart. Introduce a variety of low calorie and low-fat vegetables, fruits, and starches, as tolerated.
  3. Keep a daily record of your food intake. Include proteins and calories.
  4. Avoid skins and seeds of fruits and vegetables. These are difficult to digest and can cause problems for a smaller stomach mass.
  5. Chew food thoroughly. Chewing is the first stage of digestion, so you want to get as much of that process completed before food reaches the stomach.
  6. Avoid starchy foods and those that are naturally high in sugar. Don’t eat rice, bread, or fresh fruits.
  7. Avoid foods that are not easily chewed. This includes raw vegetables and certain meats like pork or steak. Ground meats are more easily tolerated.
  8. Stop eating when you feel full.
  9. Continue to use protein powders and shakes.
  10. Hydrate
  11. Do not use straws, drink carbonated beverages or chew ice. These activities introduce air into the digestive system. Pain and discomfort can result.
  12. Avoid sugar. Beware of sugar-containing foods, beverages, concentrated sweets, and fruit juices. Watch for added sugar in food products.
  13. Do not consume alcohol. Alcohol will absorb into your system much more rapidly than it did pre-surgery and can cause issues with mood-altering.

Suggested dietary additions during the soft food stage include:

  • Poached or hard-boiled eggs
  • Fish and shellfish
  • Chopped turkey or chicken breast
  • Soups
  • Warm cereals
  • Baked potatoes
  • Boiled pasta
  • Canned fruit and vegetables
  • Bananas

Carrying a water bottle with you can help you to remember to stay hydrated. Decaffeinated teas and coffees are allowed, at this stage.

Finally, your body will be able to consistently tolerate food. Your long term diet after gastric bypass surgery should remain at three balanced, small-portion meals with plenty of fluids throughout the day. 

Contact us to learn about how weight-loss surgery can benefit you.