Portion Sizes
After Gastric Sleeve, Bypass,
 or Band

portion plate

What are the "proper" portion sizes after gastric sleeve, gastric bypass or Lap-Band® bariatric surgery you ask?

The answer depends on 3 factors:

  • How long ago your surgery was
  • What you're eating
  • The surgery itself

3 Factors Affect Bariatric Portion Sizes

1. When You Had Your Surgery

How Long Ago Was Your Surgery?

In the early post op period, your new tiny tummy is swollen because it’s inflamed and therefore VERY limited in how much it can hold. It's usual to tolerate only a few bites, tablespoons, or ounces at a time in the beginning:

  • Sleeve: ~ 2-3 ounces
  • Band: ~ 1-2 ounces
  • Bypass: ~ 1 ounce, or 2 tablespoons

HOWEVER, as you heal and the inflammation and swelling goes down, you can slowly eat a little more. Stomach tissue is stretchy...it's meant to stretch to some degree. Portion sizes therefore continue to increase gradually throughout the first-year post op. But don’t worry…

…THIS IS NORMAL! The stomach won't stretch all the way back to where it started. 

Once healed, your pouch allows a larger, yet still limited, amount of food.

It's common to hear "you should only eat 1/4-1/2 cup of food" or "4-8 ounces" ...or something along those lines. Panic sets in if you eat more than that, and you start to wonder if your pouch really DID stretch all the way back and you're going to gain all of your weight back.

Well a very important point that's never talked about is...

2: The Texture of Food

Portion sizes after gastric sleeve, bypass, or band are greatly affected by texture of food. You can eat different portions of different textures. 

Liquids and soft mushy texture foods are easier to eat than hard, solid, dense textures.

  • This means you can eat a larger portion of cottage cheese (soft) than chicken (dense).
  • You may be able to drink an entire protein shake (liquid) but only eat ½ protein bar (solid).
  • You may be able to eat 6oz of Greek yogurt (mushy) but only 1 ounce of ground turkey (dense).
  • You can eat a larger portion of processed, packaged foods ("slider foods") than real, whole (dense) foods.

So the answer to how much you can eat largely depends on what you're eating!

Pro Tip:

If you feel like you can "eat alot," consider what you're eating.

The further out you are from surgery, the more solid foods you need to eat.

Eat real foods vs processed, packaged foods.

Different foods feel different in the stomach. Cubed chicken feels different (heavier/harder to eat) than soup or ricotta cheese feels (soft/goes down easily). So how do you know what a food feels like in your stomach? You have to pay attention!!


Mindful eating means you never decide in advance how much you're going to eat. You don't use arbitrary measures like 2 Tablespoons or 1/2 cup.

You evaluate how you feel after every single bite and gauge whether or not you should take the next bite.

The only TRUE way to know how much to eat is by eating mindfully!

3. The Surgery Itself

Portion sizes after gastric sleeve, bypass, or band depend on which of the 3 surgical procedures you have. The resulting pouch size is slightly different between the three surgeries:

How Big Your Stomach Was to Begin With

No two people have the exact size stomach. It might seem hard to believe, but the size of your stomach does not correlate with how much you weigh. 

People who are naturally thin can have the same size or even larger stomachs than people who are overweight or obese. ("Stomach" meaning the anatomical size of your stomach, not body fat around the middle that you typically think of as the "stomach.")

Bariatric surgery procedures remove or reduce a percentage of your stomach. So if you have a larger stomach to begin with and 80% is removed, you have a larger stomach left over than someone who started with a smaller stomach and had 80% removed. Make sense?

Consider this analogy:

Let's say you buy 2 apples, one the size of a large softball, and one the size of a small tennis ball. You eat only 80% of either one, and leave 20%.

The twenty percent leftover from the large softball size apple is a larger amount than the twenty percent leftover from the smaller tennis ball size apple. Got it?

The Point

Your portion sizes after gastric sleeve, bypass, or band may be different than someone you know who had the exact same surgery because the two of you "ended" with different size stomachs.

The Takeaway:
Portion Sizes After Gastric Sleeve, Bypass, or Band

It's impossible to define an absolute “right” gastric sleeve meal size or “right” portion after gastric bypass or post Lap-Band®...

…or to give an exact answer to the frequently asked question: “How big “should” meals be after bariatric surgery?!

It’s best to avoid “shoulding” on yourself.

The only TRUE way to know your portion sizes after gastric sleeve, bypass, or band is by eating mindfully. Master this skill and you'll always have perfect portions no matter how far out of surgery you are!

Practice the mindful eating steps with me. 

gastric sleeve diet
gastric bypass diet
gastric lap band diet