Gastric sleeve surgery is a clinically proven method for reducing body weight. The effectiveness of gastric sleeve surgery depends a great deal on your pre-op and post-op diet. 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. To ensure the success of your gastric sleeve surgery, it is crucial to adhere to specific dietary guidelines, especially in the period leading up to the procedure. This article provides a detailed overview of the liquid diet before gastric sleeve surgery, including its purpose, guidelines, and importance.
Understanding Gastric Sleeve Surgery
Gastric sleeve surgery, also called a gastrectomy, involves creating a small, sleeve-shaped stomach from about 15% of the original stomach volume. The rest of the organ is separated and plays no further role in the body’s digestive process. This smaller stomach reduces appetite and aids in long-term weight control.
The pre-op diet is your food-consumption plan for the period leading up to your gastric sleeve procedure. It makes the procedure safer and easier. It lowers the risk of complications. It starts you on the habits you’ll need to make a lifelong commitment to weight control. In many cases, you should begin your pre-op diet for a gastric sleeve surgery three weeks before your procedure.
The Importance of a Pre-Op Liquid Diet
The preoperative liquid diet, also known as the liver reduction diet, is an important part of the safety and effectiveness of your bariatric procedure. All patients will be placed on this two-week diet immediately before their surgical procedure. The purpose of the liquid diet is to shrink the liver and allow patient to lose some excess body fat. Secondarily, the pre-op liquid diet helps prepare patients for the dietary restrictions they will experience immediately after surgery. Doctors advise this liquid diet to help patients get the best possible results from their weight loss surgery.
A pre-bariatric surgery liquid diet is important for preparing the body to shrink the liver, decrease the fat volume around the waist, and prepare the digestive system for post-operative weight-loss changes. This diet should be followed to the letter from your doctor; when in doubt, consult with another professional. Bariatric surgery is just one step in your longer-term dedication to a more nutritional lifestyle.
Read also: Is a liquid diet right for you?
Liver Reduction
One of the primary reasons for following a pre-op liquid diet is to reduce the size of the liver. Reduces the size of the liver, which lies over the upper stomach. Reduces abdominal fat, making access to the stomach safer and easier. Thins out the wall of the stomach, making the stapling portion easier. All of this adds up to an easier and safer surgery, and results in a tighter sleeve for you! An enlarged liver can make the surgery more challenging, increasing the risk of complications. The liquid diet helps to shrink the liver, making it easier for the surgeon to access the stomach.
Weight Loss
The liquid diet also promotes weight loss before surgery. Weight loss before surgery will shrink the size of the liver. This allows for the surgeon to see the stomach better. Some studies of shown before surgery weight loss shortens OR times time as well. Weight loss before surgery reduces your risks of developing complications by lowering your BMI. This can lead to a lower BMI (Body Mass Index), further reducing the risk of complications.
Preparing for Post-Op Diet
The pre-op liquid diet also prepares patients for the dietary restrictions they will experience immediately after surgery. It helps patients adapt to the smaller portions and altered consistency of food they will be consuming post-operatively.
Guidelines for the Liquid Diet
Starting two days prior to your operation, you will begin a clear liquid diet and continue throughout the day to prepare your digestive tract for surgery. This diet ensures your stomach and intestines are mostly empty while keeping you hydrated. The liquid diet typically begins one to three weeks before the surgery date, as directed by your surgeon. The duration and specific guidelines can vary based on individual needs and the surgeon's preferences.
Clear Liquid Phase
In the initial phase, the diet consists primarily of clear liquids. A clear liquid diet limits you to options such as water, broth and plain gelatin. These are easy to digest, and they don't leave food bits in your digestive tract. Your healthcare professional may prescribe a clear liquid diet before or after some medical procedures or if you have digestive problems such as vomiting or diarrhea. A clear liquid diet can't give you all the calories and nutrients you need. Clear liquids may have some color. Liquids with some color are allowed if you can see through them. Foods can be considered liquid if they partly or completely melt to clear fluid at room temperature.
Read also: Explore the pros and cons of liquid diets
Allowed clear liquids include:
- Water
- Clear broth (chicken, beef, or vegetable)
- Sugar-free gelatin (Jell-O)
- Clear, sugar-free beverages (Crystal Light, Powerade Zero)
- Decaffeinated tea or coffee (unsweetened)
- Sugar-free popsicles
Full Liquid Phase
Two weeks before surgery. all surgical weight loss patients follow a Phase 2A meal plan. This high protein full liquid diet will allow you to lose body fat while preserving your muscle mass, which is the powerhouse of the body. As you move forward, you will move to full liquids, which include soups, smoothies, milk, and protein shakes.
Full liquids are foods that are normally liquid and foods that turn into liquid when they are at room temperature. You need to: Drink six 8 oz glasses of water each day. Take 5 to 15 minutes to drink 1 oz. Do not wait 30 minutes before or after meal to drink fluids. Sip throughout the day. Stop eating when you are full! Start taking vitamin and mineral supplements after your 1 week follow-up visit, as ordered. Follow all of the "Lifestyle Changes."
Allowed full liquids include:
- All clear liquids listed above
- Protein shakes (low-carb, high-protein)
- Sugar-free pudding (made with Fairlife or add collagen protein powder or non-fat dry milk powder for extra protein)
- Cream soups (celery, mushroom, chicken, broccoli, ect.)
- Homemade blended liquid soups (ex. Butternut squash soup, Carrot ginger soup)
- Lite yogurt (no fruit chunks)
- Milk (skim or Fairlife)
Protein Intake
Protein is a foundational part of the pre-and post-surgical diet, offering patients a greater sense of fullness while keeping sugar spikes under control. Therefore, patients will need to consume up to 80 g of protein each day. Since this is almost impossible on a liquid diet without supplementation, we recommend protein shakes 3-5 times per day. There are many protein shakes on the market, but some have significant amounts of sugar, which is counterproductive to the post-surgery program. You should try to consume 60-80 grams of protein per day.
Read also: Risks of Liquid Diets
During this period, all patients will also have to supplement their diets to avoid any nutritional deficiencies. Supplements will include a multivitamin as well as a combination calcium-and-vitamin D supplement. Other supplements will be recommended as needed, based on pre-op testing and bloodwork.
Hydration
Fluids: Consume a minimum of 64 ounces of water per day. Other fluids can also be included as long as they are: Uncarbonated, Sugar-free, Caffeine-free (examples: Crystal Light, Powerade Zero, decaf unsweet tea).
Restrictions
- Solid Foods: Do not eat any solid food the day before surgery.
- Carbonated Beverages: Avoid all carbonated fluids.
- Alcohol: Do not drink carbonated fluids such as pop, juice, or alcohol. Carbonation can cause stomach pain. These rinks have extra calories and sugar that is not needed.
- Caffeine: Wean off caffeine-containing drinks over these two weeks. You will need to avoid caffeine for the first two weeks after surgery (until the Soft Food Diet stage starts).
- Citric Acid: Do not drink anything with citric acid. The first 3 months after surgery, do not eat acidic or citrus foods such as tomatoes, lemon, orange, or lime.
- Sweets: Refined sugars, like those in candy and soft drinks, should be eliminated.
Sample Meal Plan
Here’s a sample meal plan for the pre-op liquid diet:
- Breakfast: Protein shake (at least 20 grams of protein, 10 grams of carbs or less)
- Mid-Morning: Clear broth
- Lunch: Protein shake
- Afternoon: Sugar-free gelatin
- Dinner: Cream soup (blended)
- Evening: Protein shake
Lifestyle Changes
Starting today, you agree to: Eat 3 meals a day. Eat protein and a carbohydrate choice at each meal. Eat your protein first. Take 30 minutes to eat your meal. Chew your food to a pureed/mush consistency. This takes 20 to 30 chews. Eat nutrient-dense foods such as vegetables, whole grains, fruits, and lean meats. Do not eat calorie-dense foods such as chips, cookies, crackers, ice cream, fried food, candy, hot dogs, brats, and bologna. Do not eat non-nutrient-dense foods such as pretzels, rice cakes, and animal crackers. Eat 3 milk snacks each day. Do not drink fluids 30 minutes before meals, with meals, or for 30 minutes after meals. Do not use tobacco or nicotine products. Exercise 30 minutes or more a day. Keep detailed food and activity records (bubble sheets). Bring them to each dietitian appointment. Do not use straws.
Managing Hunger and Expanding Variety
Since you will not have a tool working for you, you may feel hunger. This is expected and normal. You will likely feel real physical hunger and also “head hunger.” Head hunger is the wanting to crunch or snack on certain types of foods. You can expect to feel a certain amount of hunger and will have to manage with this.
The reality is that your variety will be limited while following the high protein liquid plan. Your surgical weight loss dietitian has provided you with a list of acceptable liquid drinks. The variety is limited, but remember this is only for a short period of time.
Day Before Surgery
The day before surgery you must only consume liquids. Do not eat any solid food the day before surgery. Around noon the day prior to your weight loss operation you will be instructed to begin bowel prep. Do not eat or drink anything, including mints or gum. Do not swallow any water while brushing your teeth and rinsing. It’s normal to feel hungry in the morning when you check into the hospital.
Other Important Pre-Op Instructions
Shower with the antibacterial soap the pre-operative nurse at the hospital gave you when you pre-registered for surgery. Thoroughly wash your entire body before rinsing, including your navel. Please inform the office if you are allergic to the specific antibacterial soap given.
Pack a bag for your hospital stay with any personal items you may need such as a contact lens container, sleep apnea mask and any daily medications you take. Leave all jewelry, credit cards and other valuable items at home. Remember to pack comfortable clothes to wear after your procedure and bring all educational materials that Dr.
Medication Changes
Medication changes before surgery Talk with your doctor about how to adjust medications, including insulin, during this low calorie, low carbohydrate diet phase. Discontinue phentermine, Ozempic®, or any other diet medication 2 weeks before surgery due to potential interactions with anesthesia. Thyroid medication should continue to be taken.
Discontinue Harmful Substances
Smoking, vaping, dipping chewing tobacco or any form of nicotine are strictly prohibited, due to the increased risks of surgical complications. You will undergo nicotine testing for confirmation before surgery will be scheduled. You will be required to commit to avoid nicotine completely after surgery as well, due to the increased risks of stomach ulcers.
Discontinue all hormonal therapy (testosterone, birth control pills) one month before surgery to reduce the risk of blood clots. If you have implantable birth control or an IUD, you do not have to have this removed.
Supplements
Discontinue all herbal supplements other than vitamins two weeks before surgery. Start bariatric vitamins at least two weeks before surgery. Include your bariatric multivitamin and calcium during this phase.
Post-Op Diet Progression
Bariatric diet progression When to start Phase of diet Today Low-calorie general diet 10 days before surgery (dietitian will tell you what day to start) Pre-surgery blended liquid diet Day of surgery No food or drink Day 1 (in the hospital) Clear liquid diet Days 2 to 14 (2 weeks) Full liquid diet Days 15 to 30 (until 1 month visit) Pureed diet (very smooth) Days 31 to 60 (after 1 month visit) Soft diet Dyas 61 to forever General diet
Potential Challenges and How to Address Them
Hunger
Some patients may feel lower energy levels because of lowered calorie consumption. Will I feel hungry? Since you will not have a tool working for you, you may feel hunger. This is expected and normal. You will likely feel real physical hunger and also “head hunger.” Head hunger is the wanting to crunch or snack on certain types of foods. What do I do if I feel hunger? You can expect to feel a certain amount of hunger and will have to manage with this.
Low Energy Levels
Some patients may experience fatigue or low energy levels due to the reduced calorie intake. It is crucial to stay hydrated and consume nutrient-rich liquids to combat this.
Taste Fatigue
Sticking to a liquid diet can become monotonous, leading to taste fatigue. Experiment with different flavors and recipes within the allowed guidelines to keep the diet interesting.
Addressing Common Misconceptions
"I can have a last meal."
It is NOT recommended to over indulge before surgery. High blood sugars the morning of surgery may result in a canceled surgery.
"Pre-operative weight loss is not important."
At present, evidences from randomized and retrospective studies do not support the hypothesis that pre-operative weight loss could improve weight loss after BS surgery, and the insurance-mandated policy of a preoperative weight loss as a pre-requisite for admission to surgery is not supported by medical evidence. On the contrary, some studies suggest that a modest weight loss of 5-10% in the immediate preoperative period could facilitate surgery and reduce the risk of complications.
The Importance of Following Instructions
How will my surgeon know if I follow the plan or not? The goal is to have weight loss. Following the liquid plan will guarantee a significant weight loss in a short period of time. It's very important that you adhere to this liquid diet according to your surgeon's instructions. There have been cases in which a patient's surgery was canceled due to noncompliance with the pre-op diet.