Your Ultimate Guide To the Bariatric Diet

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The bariatric diet is the recommended diet after undergoing gastric bypass surgery or the gastric sleeve. While it’s essentially a healthy diet it can be layered with confusion. The American Society of Metabolic Bariatric Surgery has not created universal guidelines for bariatric surgery centers to follow. Hence, each surgery center develops its own set of unique guidelines and sometimes they differ.

This article addresses what to generally expect from a long term bariatric diet. Please refer your surgery center’s guidelines for specific detail. 

What is the Bariatric Diet?

The purpose of the bariatric diet is to help patients recover safely and optimize health and weight loss after undergoing weight loss surgery. Typically, post-op bariatric patients move through four diet phases after weight loss surgery. These phases include:

Phase 1: Liquids (1-14 days)

Phase 1 will include clear liquids that are sugar-free, caffeine-free and without carbonation. Typically this will include water, herbal tea, broth or flavored sugar-free waters. This part of the diet is usually only one or two days and mimics the liver shrinking diet that helped you prepare for surgery.

You will likely begin to use an approved protein drink within two days after surgery to help you meet your protein needs. Some surgery centers allow sugar free puddings at this point or strained cream soups, which is known as the full liquid diet. This phase typically lasts about 10-14 days.

Phase 2: Pureed (2-3 weeks)

In phase 2 you begin to introduce real food back into your diet in pureed form. The purpose of this phase is to help your body transition into eating real food again. All your food must be blended to a smooth texture. Typical foods allowed during the pureed phase include plain yogurt, pureed meats such as chicken, or pureed steamed vegetables. For a more in depth look at this phase please read Your Guide to the Pureed Diet.

Phase 3:  Soft Diet (1-5 months)

During phase 3 you can begin to introduce real whole foods that are not blended. However, the texture still needs to be soft and easy for your body to digest. This would include soft meats, cooked beans, steamed veggies, peeled fruit or cottage cheese. At this point raw vegetables, and unpeeled fruits are avoided. Also starches are not suggested at this time because you need room in your pouch for protein. Surgery centers vary greatly on the length of this phase but I have witnessed it be anywhere between 2 weeks to 6 months. To learn more about phase 3 in detail please check out Your Guide to the Soft Diet

Phase 4: Regular Diet (Indefinetely)

In phase 4 you can begin to introduce all types of whole foods into your diet but it’s still important to avoid/limit processed foods to help optimize your nutrition and weight loss. Starches are eaten in limited quantities and there continues to be a high focus on protein. Most surgery centers suggest at least 3-4 oz protein per meal to help meet your protein needs.

Pear, smoked salmon and green beans in proportion to the bariatric diet

How Big Will My Portions Be on the Bariatric Diet?

Immediately after bariatric surgery, your new pouch is swollen and can only tolerate small amounts of food. Don’t be surprised if you can only handle a tablespoon of food at first. This is completely normal. As your body heals you will begin to increase your food intake.

Be aware that everyone progresses differently and your journey will be unique to you.

You’ll likely be able to gradually eat more food up to one year after surgery. At that point you will settle around eating one cup portions at each meal but this depends on the type of food. Dense proteins such as chicken are more filling than salad, crackers or soft textured proteins like yogurt.

As you’re able to eat more real food, the amount of protein drinks you drink will taper off.

How Much Protein Should I Eat on the Bariatric Diet?

The guidelines set forth by the ASMBS state that post bariatric patients should eat at least 60 g protein/day. However, many surgery centers recommend more. Protein needs depend on your height, weight, activity level and nutrition goals. If you’re a male or tall in stature your protein needs are likely higher than 60 g and may be as high as 120 g protein a day. It’s important to discuss with your surgery team what your unique protein needs are.

Once you reach about 1 year after surgery, it’s important to focus on getting protein from real food like fish or ground beef instead of protein drinks. This is will help keep you more satisfied and provide your body with a variety of nutrients that can’t be replicated with protein drinks.

How Many Carbs Should I be Eating on the Bariatric Diet?

This is the million dollar question that I receive almost everyday. And the frustrating part is that there is no clear answer. What is known is that too many carbs in the diet may hinder your weight loss.

The amount of carbs you are eating in the first few months will be very low. Since you’re saving room in your pouch for protein you’ll likely not be able to fit carbs in. Most patients are below 50 g carbs in the first few months.

As you reach 6 months, you will be able to eat a little more carbs. Ranges vary from 40-60 g carbs at this point. As your stomach size begins to increase you may be able to tolerate 75-100 g carbs/day if you’re eating protein first and whole, real foods.

Athletes may need more carbs to help fuel their workouts. I have seen some sources suggest bariatric athletes should not exceed 150 g carbs per day.

The bariatric plate method suggests to include 3-4 oz protein, one tablespoon with generic tadalafil, ⅓ cup of vegetables and 3-4 tablespoons of a healthy carb at every meal. If you are following this pattern then you will be consuming a low carb diet. Healthy carbs to focus on include:

  • Sweet potatoes
  • Fruits
  • Whole grains
  • Starchy vegetables like beans, peas or corn

Another way to look at how many carbs to eat can be based on a percentage of how many calories you are eating. General recommendations suggest to eat 40-65% of your calories from carbs. If you apply this to the bariatric population that consumes about 1000 calories a day then the carbs would be about 100 g carb/day at the low end.

Many bariatric centers suggest sticking to 75-100 g carbs per day in the maintenance phase.

But as stated before, everyone is different and professionals vary in their opinions. What is important is what works for you and your body. It is important to work with your dietitian to personalize your needs for you.

One thing that everyone can agree on, is that it’s important to limit processed carbs such as candy, cake, ice cream, pasta or white bread. This may cause dumping in post bariatric patients and inhibit your weight loss. Plus, you’ll likely eat more carbs then you intended since many of these are slider foods.

Salmon, cauliflower, and quinoa to demonstrate what is in the bariatric diet

How Many Calories Do I Need to Eat After Bariatric Surgery?

This is another popular question without a clear answer. In the early stages after surgery it’s common to consume less than 500 calories a day because the pouch is so small that it’s challenging to eat a significant amount of food.

As your pouch heals and expands you will gradually be able to eat more calories. Many surgery centers suggest keeping your calories to 900-1200 calories a day to prevent weight regain. But this highly depends on activity level. The key is to focus on high quality calories such as protein, healthy fats, vegetables, and high fiber carbs.

If you are sticking to the bariatric plate method, you’re likely within your calorie limits.

How Many Times Do I Need to Eat a Day on the Bariatric Diet?

It’s important to eat at least three meals a day after weight loss surgery. This increases your chances of meeting your protein goals at the end of the day. It may also help keep your metabolism elevated.

On a side note, your meal sizes may be much smaller than what you are used to (especially in the beginning). In fact, you may consider them a snack. Whatever you call them, it is important to eat at least three times a day.

Many bariatric post-ops need to eat 4-6 times a day to help them meet their protein needs because they cannot tolerate a lot at a time. This is normal as well. Talk to your dietitian about what may work best for you.

How Much Water Do I Need to Drink?

Many surgery centers recommend drinking at least 64 oz ounces of liquid. Drinking water may improve your metabolism and help you feel better. These liquids include sugar and caffeine free beverages. It’s also commonly suggested to not drink carbonated beverages after weight loss surgery.

It’s generally recommended not to drink with meals or 30 minutes after undergoing weight loss surgery. It may move the food through your stomach faster causing you to feel hungrier sooner. 

With the limited times that you are allowed to drink, it can be challenging to drink enough fluids after bariatric surgery. It may be helpful to carry a water bottle and use an alarm clock to help you remember to drink your fluids.

Another strategy is to have a plan. This includes writing down the times of day when you can drink. Aim to drink water at these times.

Do I Have to Take Vitamins While on the Bariatric Diet?


This is a must after weight loss surgery. Even if you have the perfect diet you are not able to absorb nutrients as efficiently as you once used to, hence you need vitamins.

Most surgery centers recommend a specially formulated bariatric vitamin. These are specifically tailored to meet your needs after bariatric surgery. The ASMBS has created a set of nutrition guidelines that are important to follow.

Likely you will need to take vitamins multiple times a day.

Do You Have Any Bariatric Recipes?

Yes. if you need a list of recipes please check out:

They are designed to be high in protein and low in processed carbs.

Do you Have a Bariatric Meal Plan?


If you haven’t already you can download my bariatric meal plan pdf here.  

What Are Some Other Tips You Can Give Me About The Bariatric Diet?

Eat Protein First

Eating protein first serves two purposes. First, you will be more likely to meet your protein goals because you will not become too full before eating it.

Second, eating protein first will help you feel fuller sooner so you’ll be less likely to overeat later. It will also help keep you fuller longer.

Chew Your Food Thoroughly

Chewing your food thoroughly will help you digest your food easier. Plus, it may help you take longer to eat to help signal to your brain you are satisfied.

Listen to Your Hunger Fullness Cues

It is important to listen to your body’s hunger and fullness cues. If you get too hungry, you may be more at risk for overeating when you do finally eat a meal. On the flip side, it’s important to notice when you are satisfied so you do not overeat.

Be Patient With Yourself

Learning to make healthy changes and listening to your body takes time and practice. Just because you had surgery does not mean you will learn everything right away. Be patient with yourself as you discover a new healthy way of eating for yourself.

Do You Need More Help?

Schedule a 20 minute discovery call with me to see if I can help you along your weight loss surgery journey. 

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Hi, I'm Kristin!

For the past seven years, I’ve worked with over a thousand pre and post-op patients to help them develop sustainable lifestyles unique to them.