Gastric bypass surgery is a drastic step taken by those who feel they’ve done everything possible to lose the weight, and still haven’t succeeded. However, the surgery comes with risks, and it isn’t reversible. Because of that, it’s extremely important for those considering the surgery to have a full understanding of the gastric bypass diet they will need to follow in order to have a safe and successful outcome.
Pre-Operative Liquid Diet
Not all surgeons require this, but most do. The average is about 1 to 2 weeks of a liquid diet prior to the surgery date.
Post-Operative Phase 1 Diet: Clear Liquids
For a period of at least one week following surgery, you will be on a strict liquid-only diet in order to allow the staple line in your stomach to heal.
During the clear liquids phase, you will only be allowed to consume liquids like water, fat-free broth, fat-free milk, and sugar-free jello. You should drink about 1 to 2 ounces of liquids per hour.
Post-Op Phase 2 Diet: Pureed Foods
The next phase, which tends to be during post-op weeks two and three, will be pureed foods and protein shakes. You should take in 60-70 grams of protein each day in the form of protein shakes, pureed meat or fish, and pureed egg whites. You’ll also need 64 ounces of clear liquids like those you drank in phase 1 (not counting the fluids from your pureed protein sources).
You should be avoiding caffeine, refined sugar, sugar alcohols, simple carbohydrates, and carbonated beverages. Foods typically allowed at this stage are egg whites, protein shakes, soft fat-free cheese, fat-free cottage cheese, and pureed soft meats and fish.
Post-Op Phase 3 Diet: Soft Foods
For the next one to two weeks you can slowly reintroduce soft foods into your diet. Foods should be easy to mash with a fork or spoon. Stick with soft lean meats and cooked vegetables, and be sure to get in your 60 to 70 grams of protein and your 64 ounces of fluids per day. A good serving size should be one to two ounces of food per meal, broken up into 3 to 6 mini meals per day. A tiny serving of healthy fats may be allowed, like a bit of ripe avocado.
Ideal foods for this phase would be lean chicken and turkey, fish, egg whites, fat-free cottage cheese, fat-free soft cheese, tofu, cucumbers, avocados, bananas, and cooked vegetables like carrots, green beans, squash, or potatoes.
Post-Op Final Phase: Solid Food
You can slowly work into solid food, adding only one new food per day, so you can see how your new stomach will handle it. Stay away from sweet and fatty foods that could cause dumping syndrome, which will make you sick and miserable. Stick with a diet of mainly vegetables, lean meats, and limited amounts of whole grains.
Eat slowly, chewing your food well, at least 15 seconds per bite. Don’t drink any water for 30 minutes before and after each meal, but make sure you’re still getting 64 ounces of water per day. Choose whole foods that are nutrient dense, and avoid processed and packaged foods. Be aware that some people have trouble digesting beef, shellfish, pork, grapes, whole grains, nuts, corn and beans.
This is the average gastric bypass diet that most bypass patients will need to follow. It’s a big lifestyle change, but if you adhere to your doctor’s guidelines, you’ll have the best outcome possible.