Diet is the mainstay of a patient who has undergone a bariatric surgery. In fact healthy eating patterns should ideally begin even before the surgery. Starting on a slightly higher protein diet with lots of fluids before the surgery helps the patient to prepare for the post-surgery diet better. A lower calorie, lower carbohydrate, higher protein diet is useful not only before the surgery but also after the surgery. Some surgeons might ask the patient to follow a liquid diet for 2 weeks before the surgery to prepare their system for transition.

Bariatric surgery decreases the stomach size and changes the way food is handled. Post bariatric surgery diet calls for introduction of foods in phases. Although the meal plan may vary from one hospital to another, and the diet plan differs from one patient to the next, the general guidelines are most often similar.
Generally, the diet pattern followed is:

• Weeks 1 & 2 – liquid diet
• Weeks 3 & 4 – semi solid diet
• Weeks 5 & 6 – soft solid diet
• Week 7 onwards – normal diet (with necessary restrictions)

Balanced diet is important at all times. All foods have to be introduced slowly. When a patient begins to eat solid foods again, feeling of fullness sets in quickly. This is because the new stomach holds only a small amount of food at first. Over a period of time, the pouch will get larger and can hold about a cup of food. It’s important for the patient to eat slowly and chew each and every bite thoroughly. Swallowing should be allowed only after the food becomes smooth. It should take about 20 to 30 minutes to finish a meal although the quantity is less. The patient should be told to stop eating as soon as he/she feels full.

As for liquids, no intake is allowed for 30 minutes after food. No fluids are allowed during meals either, because liquids tend to fill up the stomach, and this reduces the intake of healthy foods. The patient should take small sips while drinking fluids and not gulp them down. Use of straw or drinking straight from the bottle is also not advised.

Protein, vitamins and minerals are required in adequate quantities to meet the RDA. Protein is particularly important for healing and recovery. About 1200 to 1500 calories and 60 to 70 g of protein should be the goal once the patient reaches the normal diet phase. Multivitamin and multi-mineral supplements become mandatory after the surgery for life long. Foods that are high in fats, sugar or carbohydrates need to be avoided. Foods and beverages that have sweeteners like fructose or corn syrup, fruit juices, soft drinks, concentrated sweets, are also forbidden to prevent dumping syndrome. All liquids should be caffeine-free. Alcohol is best avoided. But adequate fluid intake should be ensured between meals. Keeping a food diary is useful because it aids as a monitoring guide of the food intake to the patient.

Given below is the list of guidelines that are normally advised for the patient after bariatric surgery.

Liquid diet guidelines:

• Make liquid preparations smooth and clear
• Sip slowly. Each meal should last about 30 minutes
• Stop as soon as you feel full or nauseated
• Use sugar-free, non-carbonated, caffeine-free beverages
• Begin with a tablespoon of liquid at a time and gradually progress to larger quantities

Semi solid diet guidelines:

• Aim for high protein
• Eat protein foods first
• Foods can be of sauce consistency
• Add new foods one at a time to check tolerance
• Avoid fiber
• Eat slowly; stop eating when you feel full
• Take liquids 30 minutes before or after a meal

Soft solid diet guidelines:

• Aim for high protein
• Eat protein foods first
• Add new foods one at a time to check tolerance
• Eat slowly; stop eating when you feel full
• Avoid highly refined foods, raw foods, high fat foods, high fiber foods

Normal diet guidelines:

• Use low fat, low sugar foods
• Gradually increase quantity from ¼ cup to ½ cup to ¾ cup to 1 cup
• Eat small meals
• Do not starve
• Eat slowly; chew well; stop eating when you’re full
• Avoid liquids during meals

Supplements:

• Supplements are required life-long and on a daily basis to prevent nutrient deficiencies.
• Multivitamins with iron, zinc, folic acid are usually prescribed.
• Alongside calcium, vitamin D, vitamin B12, are some of important supplements that are prescribed post bariatric surgery.
• The bariatric surgeon / physician usually advises the patient regarding the appropriate intake of supplements.

Sometimes weight gain takes place after bariatric surgery. This might be either due to too many high calorie foods or drinks, or eating too many small meals or reduced physical activity. Often, people do not believe they overeat. Sometimes the problem is not in eating more food but the wrong type of food.

Regular follow-ups with the dietitian are required to ensure weight maintenance and good eating habits. Long term goals should be kept in mind while planning a diet post bariatric surgery.

Sheela Krishnaswamy, RD
Diet, Nutrition & Wellness Consultant