Your diet after weight loss surgery is partially dependent on the type of surgery you have. Gastric bypass surgery creates a smaller stomach and allows food to bypass part of the small intestine. The surgery is designed to reduce the amount of food consumed, and the amount of calories absorbed.
If you have had – or are planning to have – gastric bypass surgery, you will feel full more quickly than you did when your stomach was its original size. After surgery, you will need to make specific changes in your diet – some short-term and some long-term – to help you achieve your weight loss goals.
Following gastric bypass surgery, you will transition through a four-phase diet from liquids to solid foods. How quickly you transition from one phase to the next is dependent on how quickly your body heals from the surgery.
Phase 1: Liquids
In the days immediately following surgery, you will be limited to a liquid diet. Foods you can eat during this phase include: broth, unsweetened fruit juice, milk, sugar-free gelatin, and strained cream soup. Do not drink any carbonated or caffeinated drinks, and only drink two to three ounces of liquid at a time, sipping slowly.
Phase 2: Pureed foods
After a few days of tolerating liquid foods, you will be able to move to pureed foods. This phase typically lasts anywhere from two to four weeks. Foods consumed in this phase should be a smooth paste or thick liquid with no solids. Many foods can be pureed in a home blender, including: lean ground meats, beans, egg whites, yogurt, come fruits and veggies, and cottage cheese. To puree these foods, blend with a liquid such as: water, fat-free milk, unsweetened fruit juice, or broth.
Phase 3: Soft solids
Once your doctor has given you the go-ahead, you will move from pureed foods to soft, solid foods, such as: canned or soft, fresh fruit; cooked veggies; ground, or finely diced meats. As a general rule of thumb, if it can be mashed with your fork, it’s soft enough to consume during this phase of your post-gastric bypass surgery diet.
Phase 4: Solid foods
Most patients following this four-phase gastric bypass surgery diet will be able to transition to solid foods after about eight weeks. Some people find that spicy foods, dairy, and crunch foods are difficult to eat or upset the stomach. As you transition to solid foods, you will want to start slowly to see what foods you are able to tolerate.
There are some foods that should be avoided – even on this stage of the gastric bypass surgery diet – including: nuts and seeds, popcorn, dried fruits, carbonated beverages, stringy vegetables like celery, broccoli, corn, cabbage, tough meats, and breads.
These phases are a general guideline for a post-gastric bypass surgery diet. Your doctor and dietitian will work closely with you to determine the diet that’s best for you following surgery. It’s important that you pay attention to what foods irritate your stomach and follow your doctor’s recommendations for your diet after weight loss surgery.