The main goal after bariatric surgery is to allow the stomach to heal while providing your body with proper nutrition. Within the first two months post-op, you will slowly progress your diet from clear liquids to a regular, healthy diet under the supervision of your surgeon and registered dietitian.
Post-Operative Food Progression After Bariatric Surgery
There is a strict food progression that begins immediately after bariatric surgery. It's important to follow this progression to avoid complications and ensure the long-term success of the operation:
Clear liquid diet — While in the hospital you will be asked to take small sips of clear liquids. These include water, broth, sugar-free gelatin, sugar-free popsicles, decaf tea, decaf coffee, and sugar-free non-carbonated beverages. You will start by drinking 1–2 ounces every hour. Once discharged, you should increase fluid intake to 3–8 ounces every hour to avoid dehydration. The goal is for you to drink 48–64 ounces daily. Straws should be avoided to prevent discomfort.
Full liquid diet — After the first week, you will add “full liquids,” such as strained low-fat cream soups, fat-free/low-fat milk (or unsweetened non-dairy milk), low-fat yogurt, and sugar-free fat-free pudding. You will start protein shakes to help meet your daily protein goal (whey protein is typically recommended after surgery). Your goal is to drink 64 oz of fluid daily.
Pourable protein — At this stage, foods need to be put in a blender to achieve a smooth baby food consistency for 3 weeks. This is necessary to avoid serious complications and to increase your tolerance to new foods. Each meal is about 2 ounces (1/4 cup) of blended protein foods. It is okay if you feel full after a few bites and cannot eat the whole 1/4 cup.
Mushy/soft diet — This stage includes foods that can be easily mashed with a fork (e.g., lean ground meats, poultry, fish, canned tuna/salmon, scrambled eggs, beans, tofu, cooked soft vegetables and fruits canned in water or natural juice). You should eat protein foods first to meet your daily protein goal. Protein shakes are still an important part of your diet. An average meal at this point is about 4 ounces (1/2 cup).
Regular diet — Usually patients are able to safely begin a regular, healthy diet at 9 weeks after weight-loss surgery. You will be encouraged to choose mostly high-protein foods and to avoid foods that are usually not well tolerated. You will continue practicing all the good eating habits you learned as you were preparing for surgery. Meals are about 4–8 ounces (1/2–1 cup). People who had a gastric bypass can sometimes be more sensitive to high-fat and high-sugar foods. This is called “dumping syndrome”. You will learn how to avoid this uncomfortable side effect.
Foods to avoid: rice, bread, pasta, dry/tough meats, high-sugar foods, high-fat foods, and fibrous vegetables (e.g., raw celery, asparagus, raw cabbage).
Beverages to avoid: carbonated beverages, whole or 2% milk, fruit juice, smoothies, energy drinks, caffeine, and alcohol.
Possible Nutrition Complications
Possible nutrition complications from bariatric surgery may include:
Nausea, vomiting, constipation, diarrhea
Dumping syndrome: a feeling of fullness and cramping which can lead to diarrhea, lightheadedness, headache, shaking, sweating, hunger, and fatigue. This may occur after eating high-sugar and/or high-fat foods or drinking while eating. Note, this side effect is more common for patients after a gastric bypass.
The team of registered dietitians will work with you to help you identify these issues and come up with ways to prevent and treat them.
Lifelong Nutrition Guidelines After Bariatric Surgery
Once you are eating a regular-textured healthy diet, our long-term eating guidelines include:
- Eat 3 meals per day at regular intervals.
- Take small bites and eat slowly (meals should last 20 minutes).
- Chew your food well (to applesauce consistency or at least 20 times).
- Separate drinking and eating (no liquids for 30 minutes before and 45 minutes after a meal).
- Drink at least 64 ounces of fluid daily.
- Listen to your body: eat when you’re hungry, stop when you’re full.
- Avoid caffeinated, sugary, and carbonated beverages.
- Avoid all alcoholic beverages completely.
- Eat protein foods first. If you are still hungry, choose veggies and fruit second.
- Avoid mindless/emotional eating.
Learn More About Bariatric Surgery
Looking for more information about weight-loss surgery?
- Attend a free live informational seminar or sign up to watch our on-demand seminar whenever it's convenient for you
- Explore our weight-loss surgery options
- Read about the surgery process for a successful outcome
- See the benefits and risks of weight-loss surgery
- Get answers to frequently asked questions about bariatric surgery
- Learn about insurance coverage for surgery