Diet Following Bariatric Surgery

The bariatric diet is designed to provide fluids and nourishment while promoting weight loss after bariatric surgery. The diet is divided into 3 stages. The rate of progression varies based on individual food tolerance.


The diet following surgery is divided into 3 stages to allow a gradual adjustment. It is very important to the success of your surgery to:

  • Progress to each stage slowly.

  • Eat at set times.

  • Chew food well and stop eating when you are full.

  • Not drink liquids 30 minutes before and after meals.

If you feel tightness or pressure in your chest, that means you are full. Wait 30 minutes before you try to eat again.


  • The diet begins the day of surgery. It will last about 1 to 2 weeks after surgery. Your surgeon may have individual guidelines for you about specific foods or the progression of your diet. Follow your surgeon's guidelines. 

  • If clear liquids are well-tolerated without vomiting, your caregiver will add a 4 oz to 6 oz high protein, low-calorie liquid supplement. You could add this to your meal plan 3 times daily. You will need at least 60 g to 80 g of protein daily or as determined by your Registered Dietitian.

  • Guidelines for choosing a protein supplement include:

  • At least 15 g of protein per 8 oz serving.

  • Less than 20 g total carbohydrate per 8 oz serving.

  • Less than 5 g fat per 8 oz serving.

  • Avoid carbonated beverages, caffeine, alcohol, and concentrated sweets such as sugar, cakes, and cookies.

  • Right after surgery, you may only be able to eat 3 to 4 tsp per meal. Your maximum volume should not exceed ¼ to ½ cup total. Do not eat or drink more than 1 oz or 2 tbs every 15 minutes.

  • Take a chewable multivitamin and mineral supplement.

  • Drink at least 48 oz of fluid daily, which includes your protein supplement.

Food and beverages from the list below are allowed at set times (for example at 8 AM, 12 noon, or 5 PM):

  • Decaffeinated coffee or tea.

  • 100% fruit juice.

  • Diet or sugar-free drinks.

  • Broth.

  • Blenderized soup.

  • Skim milk or lactose-free milk.

  • Sugar-free gelatin dessert or frozen ice pops.

  • Mashed potatoes.

  • Yogurt (artificially sweetened).

  • Sugar-free pudding.

  • Blended low-fat cottage cheese.

  • Unsweetened applesauce, grits, or hot wheat cereal.

Four to six ounces of a liquid protein supplement from the list below is recommended for snacks at 10 AM, 2 PM, and 8 PM.


About 2 weeks after surgery, your caregiver will progress your diet to this stage. Foods may need to be blended to the consistency of applesauce. Choose low-fat foods (less than 5 g of fat per serving) and avoid concentrated sweets and sugar (less than 10 g of sugar per serving). Meals should not exceed ½ to ¾ cup total. This stage will last about 4 weeks. It is recommended that you meet with your dietitian at this stage to begin preparation for the last stage.

This stage consists of 3 meals a day with a liquid protein supplement between meals twice daily. Do not drink liquids with foods. You must wait 30 minutes for the stomach pouch to empty before drinking. Chew food well. The food must be almost liquified before swallowing.

Soft foods from the list below can now be slowly added to your diet:

  • Soft fruit (soft canned fruit in light syrup or natural juice, banana, melon, peaches, pears, or strawberries).

  • Cooked vegetables.

  • Toast or crackers (becomes soft after chewing 20 times).

  • Hot wheat cereal.

  • Fish.

  • Eggs (scrambled, soft-boiled).


About 6 to 8 weeks after surgery, you will be advanced to food that is regular in texture. This diet should include all food groups. The diet will continue to promote weight loss. Meals should not exceed ¾ to 1 cup total. Your dietitian will be available to assist you in meal planning and additional behavioral strategies to make this final stage a long-term success.

Slowly add foods of regular consistency and remember:

  • Eat only at your chosen meal times.

  • Minimize drinking with meals. You should drink 30 minutes before eating. Do not start drinking again for about 2 hours after eating.

  • Chew food well. Take small bites.

  • Think about the portion size of a healthy frozen meal. You will be able to eat most of this.

  • Make sure your meal is balanced with starch, protein, fruits, and vegetables.

  • When you feel full, stop eating.