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Gastric Bypass Diet, Ambulatory Care

A gastric bypass diet

keeps your calorie intake low so you can lose weight. It also helps you to develop healthy eating habits and heal after surgery. There are several stages of the diet that you will have to follow after surgery before you can start eating solid foods. Your dietitian will tell you when you can move from one stage to another and what foods to choose at each stage.

General guidelines to follow while you are on the gastric bypass diet:

  • Take your vitamins and mineral supplements every day as directed. After your surgery, your body will not absorb enough vitamins and minerals from the food you eat. You will need to take these supplements for the rest of your life.
  • Drink at least 48 to 64 ounces (8 cups) of liquids each day. To get enough liquids, it may be helpful to sip 1 cup of liquid over an hour. Stop drinking liquids within 30 to 60 minutes before you next meal. Sip liquids slowly. Do not use straws. Do not drink carbonated drinks or alcohol.
  • Drink liquids between meals only. Drinking liquids with meals can cause you to get full too quickly and not eat enough food. Wait at least 30 minutes until after your meal before you drink liquids.
  • Stop eating when you start to feel full. If you do not stop when you feel full, you may vomit. Your stomach pouch can also stretch if you eat too much. Chew your food very well and eat slowly, taking about 15 to 20 minutes to eat your meal.
  • Avoid high-fat foods and sweets. Sweets include sugar, honey, jam, jelly, cake, candy, or cookies. High-fat foods include fried foods, bacon, sausage, or fatty meats. They also include butter, margarine, regular mayonnaise, and sour cream. Other high-fat foods and sweets include whole milk, ice cream, cakes, cookies, and desserts. These foods can cause symptoms referred to as dumping syndrome. Symptoms include nausea, vomiting, or diarrhea. Sweets and high-fat foods are also low in nutrients and high in calories. They can cause you to regain weight.

First stage of the gastric bypass diet:

You may only be allowed to have clear liquids in the first day or two after surgery. For the next 1 to 2 weeks after surgery, you will need to follow a full liquid diet.

  • Eat foods that are liquid or semi-liquid at room temperature. Examples include broth, unsweetened juice, sugar-free gelatin, low-fat milk, and strained cream soup. Other foods include yogurt, pudding, or custard low in fat and sugar.
  • Eat 5 or 6 small meals each day. Eat only 2 to 4 tablespoons for each meal. This will help to avoid stretching your small stomach pouch.
  • Get enough protein in your meals and eat protein foods first. Examples of high-protein foods you can eat include yogurt or pudding. You can add extra protein to milk, protein, soups, or yogurt by adding protein powder.
  • Sip liquids slowly to avoid vomiting.

Second stage of the gastric bypass diet:

When you are able to tolerate foods, you may begin eating pureed or blended foods. These foods should have the same consistency as applesauce or pudding. This phase will last about 2 weeks.

  • Drink 24 ounces of sugar-free liquids. Examples include water, decaffeinated coffee or tea, flat soda, or low-calorie cranberry juice. Broth and sugar-free gelatin and popsicles are other examples. Sip liquids slowly. Do not drink from a straw.
  • Drink 24 ounces of high-protein drinks or strained cream soups.
  • Eat 6 small meals each day. Eat only 60 to 90 ml of pureed food for each meal. Use a liquid measuring cup to make sure you eat the right amount. Examples of foods you can eat include strained, pureed, blended, and liquid foods that are low in fat and sugar.
  • Eat pureed protein foods first. Some examples of protein foods include cottage cheese, scrambled eggs, and pureed meat, fish, and poultry (turkey or chicken). Next, eat vegetables and fruit. Eat starchy potatoes and carbohydrate foods, such as cooked cereal, last.
  • Do not chew gum. Gum can block your stomach opening if you swallow your gum by accident.

Third stage of the gastric bypass diet:

During the third stage, you will be able to eat soft foods. The goal of this stage is to help you move towards eating solid food. This stage may last 1 to 2 months.

  • Eat 5 small meals each day. Eat ⅓ to ½ cup of soft foods for each meal. Eat slowly and chew your food very well.
  • Eat protein foods first. Some examples include low-fat, low-sugar yogurt, low-fat cottage cheese, and shredded low-fat cheese. Other examples include tuna packed in water and skinless chicken or turkey cooked until very tender and cut into small pieces. You can also add protein powder to foods to increase the amount of protein you eat.
  • Choose healthy foods. Examples of soft, healthy foods include cream of wheat, oatmeal, and cooked tender vegetables without peels or seeds. You can also eat ripe bananas, fruit canned in its own juice, and low-fat soups.
  • Avoid sticky, crunchy, and tough foods. Sticky foods include sticky or sweet rice, dried fruits, pastas, and high-fat cheese. Soft bread can become a sticky food because it can make a dough ball in your stomach. This dough ball can block the opening from your stomach pouch to your intestines. Crunchy foods include granola, raw vegetables, nuts, popcorn, and chips. Avoid tough or chewy meat.
  • Avoid foods with seeds, peels, or husks. Examples include strawberries and other berries, corn (unless it is pureed), and peas (unless it is pureed.)

Fourth stage of the gastric bypass diet:

About 2 months after your surgery, you will be able to start eating regular solid foods. Start eating small amounts of solid foods by eating 1 or 2 foods at each meal. Over time, you can slowly add more foods.

  • Choose healthy and easy-to-digest foods. Include a protein food for each meal and snack. Choose tender, well-cooked meats, poultry, fish, eggs, and soy foods. Do not add fat when preparing these foods. Include fruits, cooked vegetables (without seeds or skins), and carbohydrates. Choose carbohydrates with less than 2 grams of fiber per serving because they may be easier for you to digest.
  • Avoid foods that may be hard for you to digest or tolerate. These foods include fried or tough meats such as steaks or pork chops. Certain carbohydrates such as whole-grain cereals, granola, whole-grain bread, and white bread may be hard for you to digest. Other foods include raw fruits and vegetables, highly seasoned or spicy foods, and carbonated drinks.

Follow up with your healthcare provider as directed:

Write down your questions so you remember to ask them during your visits.

Care Agreement

You have the right to help plan your care. Discuss treatment options with your caregivers to decide what care you want to receive. You always have the right to refuse treatment. The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.