Bariatric Liquid Diet before Weight loss surgery
Pre Weight Loss Surgery
Bariatric Liquid Diet Before Weight Loss Surgery

Before weight loss surgery, all patients must adhere to a two-week liquid diet no matter the type of bariatric procedure being performed. The thought of drinking only liquids for two weeks sounds horrible and quite intimidating. But in this blog, we hope to educate you on the purpose of the liquid diet, the dangers of not adhering to the diet, and how to follow the diet. So grab your drink and take a seat; let’s dive in! 

As a bariatric dietitian, I understand how difficult it can be to even think about giving up solid foods in preparation for weight loss surgery. I have seen many patients struggle during these two weeks, and I do feel for them. However, despite what you may think, this is not to torture you! In fact, we require patients to only consume liquids before surgery to limit the procedure’s risk. 

Purpose of the Bariatric Pre-Op Liquid Diet

Prior to surgery, many patients will have excess fat sitting around and/or in their liver. In order to effectively reach the stomach to perform the bariatric procedure, the surgeon has to move the liver. And the larger the liver is, combined with the fat in and around it, the harder it is for the surgeon to safely and effectively maneuver around it. 

This can result in more time that the patient will be under anesthesia, significantly increasing their risk of complications, not to mention their medical bills. 

On the two-week liquid diet, patients lose enough weight to shrink the liver and limit the amount of time the surgeon will have to spend moving around the liver. 

The Pre-Op Liquid Diet Meal Plan

The pre-op liquid diet will consist of approved protein shakes, sugar-free beverages, sugar-free gelatin, sugar-free popsicles, and broth.We always recommend that our patients consume five protein shakes a day and consume at least 64 ounces of sugar-free liquids. Patients cannot consume carbonated beverages such as sodas, sparkling waters, milk or alcohol, etc., and all drinks should contain no more than 10 calories per serving. We also recommend that patients limit their caffeine consumption to two 8-ounce servings a day—all you coffee lovers can still enjoy your cup of joe (with sugar-free sweetener, not sugar).

*This plan does not need to be followed precisely. You can adjust the times based on your own schedule. 

*This plan is based on the liquid diet our practice requires patients to do and is a case-by-case diet plan. Therefore we recommend you talk with your surgeon about what you should be consuming leading up to surgery.

What to Expect with the Pre-Op Liquid Diet

When you restrict the total calories and carbohydrates you consume in a day to an extremely low amount, some patients may experience symptoms.

Some of the symptoms you can expect to experience include:

  • Extreme Hunger Pains
  • Fatigue
  • Headaches
  • Nausea, Constipation, Diarrhea
  • Mood Swings

The symptoms listed above are completely normal, and they should subside within 3 to 4 days, once your body gets used to consuming so few calories and carbohydrates. Drinking 64 oz of sugar-free beverages and broth can help with the severity of these symptoms.

Success Tips for the Pre-Op Liquid Diet

The pre-operative liquid diet is hard—there is no doubt about it! Therefore, we highly recommend that our patients mentally and physically prepare themselves for the challenge ahead.

1. Plan ahead for success.

Leading up to the days you will be participating in the liquid diet, we recommend that you go to the grocery store to stock up on all the items you will need throughout the two weeks. Waiting to buy the protein shakes, gelatin, and broths until the last minute can lead to failure in adhering to the plan. You want to make sure you set yourself up for success from day one.

2. Find a support and accountability system.

We recommend that bariatric patients find a support system; it can be friends, family, or a group of current/past patients at your bariatric clinic. By enlisting support, you are not only holding yourself accountable, but others are holding you accountable. We have seen it first hand; patients who decide to do it all on their own (pre and post-op meal plans) are not as successful with their weight loss as those are who find support. 

3. Remember, it’s temporary.

The two-week liquid diet can be daunting. It is critical that you mentally prepare yourself for the challenge. Tell yourself, this is temporary, and it is a part of a bigger plan! 

4. Ignore the numbers on the scale.

Although the liquid diet is in place to lose weight rapidly before surgery, don’t get caught up on the number on the scale. If you see that you aren’t losing weight like you want to, you may be more inclined to start cheating because “what difference does it make anyway?” 

We know that the pre-op liquid diet can be intimidating, especially if you have never been on a highly restrictive diet plan before. However, you want to be sure that you are fully committed to the pre-op liquid diet, or else your surgeon may have to cancel or reschedule your surgery. The pre-op liquid diet is a critical step leading up to the weight loss surgery, and all patients have to participate in it—so you are not alone! 

Bariatric Nutrition Guide
Complete Bariatric Nutrition Guide
Everything you need to know about bariatric nutrition pre-op and post-op and nutrition basics, tailored explicitly to bariatric patients.
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