When Can I Start to Eat Carbohydrates After Bariatric Surgery?

Published March 18, 2021 By Anne Cook Carroll, MS, RDN

What is a carbohydrate?

Carbohydrates are compounds occurring in foods (including sugar, starch and cellulose) that breakdown into glucose molecules in the body, providing a source of energy. There are many sources of carbohydrates including: grains (bread, rice, crackers, cereal), dairy (milk, yogurt, ice cream), legumes (beans), starchy vegetables (potato, corn), and sugary sweets (soda, juice, candy, cookies, baked desserts). Not all carbohydrates are created equal from a nutritional standpoint. High-fiber, nutrient dense foods like whole-grains, non-fat dairy, legumes, fruits and vegetables should be consumed in balanced portions, while concentrated sweets and simple-carbohydrates (like white bread, rice, candy, soda and pasta) should be avoided.

The introduction of carbohydrates into your diet after surgery should be assessed on an individual basis based on tolerance levels, weight loss goals and overall adequacy of your diet. In general, some carbohydrates can start to be introduced in the full-liquid phase of the diet (first 2 weeks post-op) in the form of protein shakes, protein powder based smoothies, and low-fat, low-sugar yogurt and milk. These foods are relatively low in carbohydrates and contain a high amount of protein. Carbohydrates in the form of pureed fruits, vegetables and legumes can start to be introduced in the pureed phase of the diet (weeks 3-4 post-op) in 1 tbsp amounts per meal. Foods like skinless potatoes, well-cooked vegetables and soft noodles can start to be introduced at the soft food phase (weeks 5-6 post-op), in 2 tbsp amounts per meal. 

Avoid bread and rice until 8-10 weeks after surgery as they are considered high-risk foods that can get stuck in our GI tract. Be sure to speak to your doctor and dietitian about when this might be appropriate for you. They also provide lower nutritional value and can lead to weight gain, so they should only be consumed in small amounts. In all postoperative phases, we want to be sure we are prioritizing protein over carbohydrates and fat.

Carbohydrate Daily Intake Guidelines 3-months after surgery:

Vegetables and Fruits​ – 2 to 3 servings each day

1 serving is typically 1⁄2 – 1 cup. Keep in mind that 1 cup is about the size of a baseball.

  • 1⁄2 cup raw or cooked vegetables
  • 1⁄2 cup tomato or vegetable juice
  • 1 small fresh fruit
  • 1⁄2 cup canned fruit (in its own juice) or frozen fruit
  • 1 cup cubed fruit

Note: Continue to be careful with skins and seeds, high fiber vegetables, and dried fruits. 

Breads, Grains and Cereals ​– 2 to 5 servings each day, 1 serving is:

  • 1 slice bread (whole grain)
  • 1⁄2 cup cooked pasta (whole wheat better than plain)
  • 1/3 cup cooked rice (brown better than white)
  • 3⁄4 cup dry cereal
  • 4-6 saltines

Team Tip from Dr. Daniel J. Rosen:

Certain carbs will be automatically problematic after Bariatric surgery because of their propensity to get “stuck” regardless of the procedure, be it sleeve, bypass, or band.   Bread, rice, pasta is so gummy that it tends to stick and clump together when chewed and swallowed and can then obstruct the narrowed portion of the stomach that creates the “restrictive” component of any weight loss surgery.  Healthy complex carbs can typically be reintroduce a few weeks after surgery in the puree phase.  Examples would include fruit, oatmeal, farina or refried beans.