How to Eat After Bariatric Surgery – All You Need to Know

After you have weight loss surgery, it’s important that you change both what and how you eat in order to help prevent complications, weight regain, and malnutrition. This includes:

  • Preparing your food properly
  • Controlling your portion sizes
  • Eating slowly and chewing thoroughly
  • No drinking before, during, or after meals
  • Paying close attention to how your body feels after you eat

Read the sections below for everything you need to know about eating the right way after weight loss surgery.


Click on any of the topics below to jump directly to that section

  1. How to Prepare Food
  2. Portion Sizes
  3. Eating Technique
  4. Drinking
  5. Identifying Problems

How to Prepare Food


  • Use a diet journal
  • Only buy foods on your list
  • Only eat what you’ve planned
  • Use a food scale to measure ingredients & portion sizes

Preparing your own food is one of the best ways to avoid harmful ingredients and stay on the path towards your goal weight. It’s also a great way to make your new bariatric diet taste good!

If you don’t know how to cook, we strongly suggest taking an entry level cooking class to learn the basics. Some weight loss surgery clinics offer cooking classes for their patients, so talk with your surgeon to see if your team offers them. If they don’t, they may know of a nearby team with classes you can join.

There are also several good cook books specifically written specifically for the bariatric surgery patient, including…

If pouring a bowl of cereal is the extent of your meal-preparation ability or if you prefer having pre-made meals readily available in your freezer, there are several reliable services that will deliver high-quality custom meals right to your doorstep for a reasonable price.

When you’re ready to hit the kitchen or order your food…

  1. Use a good free diet journal to plan and record your meals.
    A food journal is an invaluable tool that will let you…
    • Plan all of your meals ahead of time
    • Set goals and record your progress
    • Identify and avoid “trigger foods” that cause problems
    • Work more effectively with your dietitian or nutritionist

  2. When you go to the grocery store, only buy the foods that you have planned.
    If you don’t buy it, you can’t eat it. To help yourself through this, do not go to the store when you’re hungry.

  3. Only eat what you’ve planned, when you’ve planned.
  4. Again, your journal should be your place to plan your meals.
    There should be absolutely no snacking allowed between meals unless it is approved by your dietitian or nutritionist (one scheduled healthy snack a day may be okay). Straying from your plan is a sure-fire way to experience weight gain after bariatric surgery.

  5. Use a food scale to measure your ingredients and portion sizes.With a stomach the size of a golf ball, you’ll need to make sure that you’re getting all of the nutrients you need before you get full. A good food scale is the only way to be sure.

Portion Sizes


  • About 4oz (113g) per meal
  • Stop eating before you feel full

Every patient’s stomach size is a little different after bariatric surgery, but it’s likely that you’ll be eating around 4 ounces of food per meal (if you’re a lap band patient and can eat more than this, you may need a fill). That’s equal to about one cup.

The trick is to stop eating before you feel full, which can be tough at first considering how small your meals are compared to what they used to be.

If you do not stop eating before you feel full, there’s a good chance you’ll experience problems such as vomiting, diarrhea, constipation or difficulty swallowing. It can also cause your stomach to stretch and lead to weight regain.

Learn the amount you can eat comfortably at each meal without feeling full and weigh your portions out using your food scale.

Want to try an extremely effective mind game? Tiny amounts of food on a normal-sized plate will make your mind think that it’s not getting enough. Use small plates and small utensils while eating – you’ll be surprised how much it helps.


Eating Technique


  • Cut food into tiny bites
  • Eat slowly
  • Chew thoroughly

Eating slooooowly and chewing your food thoroughly has a few big advantages…

  • Gives your stomach time to send “full” impulses to your brain.
  • Allows you to savor the food you eat.
  • Breaking the food down before swallowing gives your digestive system a head-start. This means more nutrient absorption and fewer bowel function problems.
  • Eliminates awkwardness while eating with family or friends. If you inhale your 4 ounces of food, you’ll be sitting there with an empty plate while everyone else eats.

Take your time, cut tiny portions, chew well (your food should have no hard or stringy parts when your done chewing) and put down your fork between bites. Synchronizing the amount of time it takes to eat your meals with others at the table is a good way to keep a healthy pace.

Eating a nutrient-rich diet and exercising regularly not only help you hit your goal weight sooner, avoid complications and keep you feeling good… they also make you feel full sooner by telling your brain that your body’s gotten what it needs.

See our Bariatric Diet and Exercise for Bariatric Surgery Patients sections for guidance about healthy meals and tips to keep you on track.



  • NO drinking with meals
  • Drink cup of water 20 minutes before meals
  • Wait at least one hour after eating

"Drinking a cup of cool water 15 to 20 minutes before your meal can make you feel full sooner."

Do not drink during meals or an hour afterwards… ever.

It will wash your small meals right through your stomach and leave you feeling hungry. It can also cause unpleasant side effects like dumping syndrome.

However, drinking a cup of cool water 15 to 20 minutes before your meal can be a good thing. It can make you feel full sooner after you start to eat.


Identifying Problems


  • Feeling full
  • Chest discomfort
  • Nausea or vomiting
  • Gas, bloating, or cramping
  • Abdominal pain

Sometimes it takes a while to home in on the right portion sizes and to figure out which foods don’t agree with your new stomach. Pay attention to the following symptoms if they come up and adjust your bariatric diet accordingly…

  • Feeling full

    In the time before surgery, feeling full was a normal part of eating. After surgery you want to avoid it. Stop eating before you feel full to prevent vomiting and other problems.

  • Chest discomfort, pain or pressure

    If you experience these, immediately go to your food journal and note exactly what you ate and how much you ate of each ingredient. If the feeling doesn’t go away quickly or if you continue to experience it after your meals despite reducing your portion sizes or what you eat, call your doctor right away.

  • Nausea or vomiting

    If this happens on a one-off basis and subsides quickly, it’s probably due to something you ate or dehydration. If it comes after a meal, again, jot down what you ate for later reference. Dehydration could occur if you don’t get your 64 ounces of fluids per day as reviewed on our Bariatric Diet page. Adjust your fluid intake accordingly.

    Swallowing nasal drip could also be the culprit. If your sinuses are dripping after surgery, several over the counter medications can address it. Call your doctor for recommendations, as many medications can be harmful to your new stomach.

  • Gas, Bloating and/or Cramping

    Can also be caused by certain foods. You’ll need to determine the cause and either keep that food out of your diet or prepare it differently.

  • Continual vomiting and/or abdominal pain

    Call your doctor right away. It may be nothing, but it could be one of several bariatric surgery complications that requires immediate medical attention.


* Disclaimers: Content: The information contained in this website is provided for general information purposes and your specific results may vary depending on a variety of circumstances. It is not intended as nor should be relied upon as medical advice. Rather, it is designed to support, not replace, the relationship that exists between a patient/site visitor and his/her existing physician(s). Before you use any of the information provided in the site, you should seek the advice of a qualified medical, dietary, fitness or other appropriate professional. Advertising: Bariatric Surgery Source, LLC has entered into referral and advertising arrangements with certain medical practices, original equipment manufacturers, and financial companies under which we receive compensation (in the form of flat fees per qualifying action) when you click on links to our partners and/or submit information. This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply. Read More

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