The alterations made to the stomach’s size and digestion process during bariatric surgery adjusts how, when, and what patients should eat. Dietary guidelines vary based on the type of procedure and doctor. In general, the decrease in the stomach’s capacity to hold food prevents post-opt patients from over- eating without feeling nauseous. Patients readjust to eating solid foods by learning to eat slowly, chewing foods 20+ times to puree before swallowing, and pausing between bites. Nutritionists often recommend eating protein first at each meal, eating 3 smaller meals and 2 snacks each day, and never skipping a meal or snack. Fluids are to be consumed at non-eating times to avoid feeling premature fullness at meals. Most patients avoid carbonation for 6 months; gastric bypass patients must avoid it forever. To avoid the possibility of gulping air, patients should not use straws. Prescriptions for dietary supplements and multi- vitamins are included in the ongoing aftercare. Gastric bypass patients must take sublingual B12 and calcium citrate in addition to a multi-vitamin daily.
Patients advance gradually through four or five diet phases, depending on the type of bariatric surgery, to readjust their altered stomachs to this new bariatric eating. Nutritional care is critical to ensure adequate energy and nutrients, support tissue healing, and preserve lean body mass during weight loss. During Day 1 and Day 2 after all bariatric surgeries, or Phase 1, patients are limited to clear liquids. Sugar-free and low sugar clear liquids supply fluid, electrolytes, energy, and start to encourage stomach activity. There are no calorie minimums during Phase 1 but patients should ingest at least 32 fluid ounces each day. Clear liquid diets are nutritionally inadequate and must include vitamins and supplements.
During Phase 2, all liquids are permitted. Patients should consume 500 – 1000 calories with a 40 protein grams minimum for women and a 60 protein grams for men. Phase 2 generally lasts from Day 3 to Day 7 - Day14 (depending on the doctor /nutritionist) for Lap-Band patients and from Day 3 to Day 14 for gastric bypass and gastric sleeve patients. Common foods in this phase include milk, vegetable juice, strained cream soups, artificially sweetened yogurts, and sugar-free puddings.
Phase 3 reintroduces soft foods. In this phase, raw fruits and vegetables, crunchy foods, nuts, and popcorn are not permitted. Patients eat only soft foods like eggs, soft cheese, fruits, and hot cereals that can be pureed in their months. The calorie intake should range from 1,000 to 1,400 calories with a 40% carbohydrate, 30 % protein, and 30% fat breakdown. Phase 3 continues from the end of Phase 2 until the 2 month mark for Lap-Band and gastric sleeve patients. For gastric bypass patients, Day 15 to 1 month after surgery is Phase 3 and permits 2 ounces of pureed proteins and 1 - 2 ounces of pureed vegetables and fruits per day. At 1 month to 2 months, Phase 4 for gastric bypass, patients then expand their diet to include all soft foods.
In Phase 4, for LAP-BAND and gastric sleeve patients, and Phase 5, for gastric bypass patients, a regular diet begins around 2 months for all bariatric surgery patients and should continue forever. Dieticians recommend no more than 400 calories per meal with a 30% protein, 40% carbohydrate, and 30% fat nutritional breakdown. Regular diet for patients should be low in omega-6, high in omega- 3, and include 25 grams of protein per day or more. Advancement to the regular diet phase is advised at the recommendation of a doctor or dietitian. Doctors commonly conduct nutritional consultations individually at 1-2 weeks, 1, 2, 3, 6, and 9 months, and then yearly.
Source: ASMBS Allied Health Nutritional Guidelines for the Surgical Weight Loss Patients