Patients will typically be required to undergo two diet regimens, one before surgery (pre-op) and one after (post-op). The main purpose of the bariatric surgery diet is to decrease surgical risks that come as a result of too much fat surrounding the abdominal and the liver. Both are crucial to qualifying for bariatric surgery and succeeding at your weight loss goals.

This page is a brief guide to what you can expect from the dieting process before and after surgery. We specifically left out surgery types, but all patients will undergo similar dieting regimens. Here is what you can expect:

Pre-Op Dieting and Nutrition

Bariatric Surgery Pre-Op Diet - The Liquid Diet

Some patients will be required to undergo a strict dieting plan for several weeks before the surgery date. In some cases, patients will need to be on a diet for several months before surgery. The main purpose of the pre-op diet is not to lose weight, but to decrease the fat that surrounds the stomach and liver.

What will I eat?

The diet is a low-calorie, high protein diet that will need to be strictly maintained. Patients will normally consume 800 to 1200 calories per day for two weeks or in some cases much longer. The diet will normally be high in protein and low in sugar and fat.

The diet prescribed by surgeons will often be predominately liquid which will be easy for patients to consume the required protein intake. Patients should also avoid sugary drinks including soda, juices, and alcohol. Patients should also try to consume lean meats and high-fiber foods: chicken breast, eggs, oatmeal, etc.

Post-Op Dieting and Nutrition

After surgery, patients will again be put on a strict dieting plan. This time, it’s especially important for patients to follow the physician’s orders and guidelines during the first few weeks after surgery. Failure could delay healing and cause serious complications, or malnutrition.

Complications that Can Arise By Not Following Diet Plan Includes: Vomiting, Lap-Band displacement, disruption internally, pain, stomach stretching, bleeding at the sutures, stomach expansion, and stomach blockage.

Bariatric Surgery Dieting (Before and After)

What will I eat?

First Few Weeks: Patients will likely be put on a strict liquid-based diet. This diet is specifically designed to help the patient’s stomach heal. Overall, patients will be required to consume protein-rich liquids and at least 64-ounces of water throughout the day.

Clear Liquid Diet includes liquids like water, tea, diluted juices, protein fruit drinks, non-sugary or non-carbonated drinks.

Two Weeks After Surgery: Past the first few weeks patients will be allowed to consume more and have a larger variety of foods, including pureed food. Other liquids include low-fat milk, soups, yogurt, and sugar-free jello.

After a few months, patients will be able to incorporate soft foods, more pureed foods, and eventually solid foods.

Each patient will be on a different schedule based on their tolerance and recovery. It will also be based on which surgery type the patient has undergone (gastric sleeve, gastric bypass, gastric banding, gastric plication). Patients with a gastric sleeve will most likely be able to consume a longer list of foods than a gastric banding patient.

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