Pre-Op Guide: What to Eat Before Weight Loss Surgery

September 15, 2017 - by - in Nutrition

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About two to three weeks prior to any type of weight loss surgery, most physicians will have their patients go on a special pre-op diet. Doing so helps improve the safety of the surgical procedure and makes it go smoother for the surgeon and patient.

Why a pre-op diet is necessary

  • The diet’s purpose is to shrink the liver and reduce abdominal fat, which decreases the risk of complications during the surgery, according to the American Society for Metabolic and Bariatric Surgery.
  • After your bariatric surgery, you will need to follow a post-op diet to allow your stomach to completely heal and lose weight safely and effectively. This often consists of a diet that’s similar to the one you’ll follow before the surgery which means the good news about a pre-op diet is that it prepares you for what you’ll need to follow after the surgery. 
  • Following a pre-op diet also keeps you healthier post-op. This study of 881 bariatric surgery patients found that preoperative weight loss corresponds with fewer complications after surgery.

In addition, if your bariatric surgery is covered by insurance, your carrier may require you to go on a special diet up to six months before the surgery to receive coverage, as demonstration of your commitment to learn about nutrition and go to weight loss appointments.

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If you’re considering bariatric surgery for weight loss and improved health, here is the type of pre-op diet you can expect to follow in the up to three weeks prior to the surgery.

What you can eat before bariatric surgery

Pre-Op Guide: What to Eat Before Weight Loss Surgery

While you may be tempted to binge on your favorite fatty, high-sugar or high-carb foods right before the surgery, introducing healthy options before the surgery helps you maintain your weight loss after it’s done. 

Depending on your size, the typical daily caloric intake pre-op will be between 800 to 1,200 calories a day, and most of those will be consumed via liquids. You’ll also want to get between 70 to 120 grams of protein, depending on your physician’s recommendations. 

Because the calorie limit is likely much smaller than what patients are used to, staying hydrated throughout the day is key to satiate hunger, which is temporary and will subside over time. The following food items will help reduce liver size and fatty tissue and prepare you for a healthy lifestyle; try these in the two to three weeks before your surgery:

  • Protein shakes. Protein helps you retain muscle and increases metabolism speeds. There are protein shakes on the market designed specifically for bariatric surgery patients which serve as meal replacements and can be mixed with water or skim, soy or nut milk.
  • Clear liquids. Besides water, you may drink low-calorie liquids like non-sugary water flavor enhancers as well as low-calorie sports drinks. Vegetable juice, vegetable broth or bone broth, which are savory low-calorie options to stave off hunger, may also be consumed.
  • Caffeine-free coffee and tea. These drinks must have no added sugar to them. Additions that are OK include small amounts of sugar-free sweetener and soy, skim or nut milk.
  • Sugar-free snacks. Sugar-free gelatin or popsicles may be consumed sparingly, up to once a day, before the surgery.
  • Low-calorie soups. Avoid soups with carb-heavy foods like pasta in them, and aim for vegetable or broth-dominant soups.

Depending on your body mass index, you may be permitted to eat some lean meats or protein-rich foods like nuts in the early days you’re pre-op. No matter what size you are, expect to be liquid-only for at least a week before your surgery and immediately after. The earlier you can adopt a diet using mostly the foods above, the better you prepare your body to be used to the diet immediately post-op and beyond.

Avoid these foods before weight loss surgery

A last hurrah of all your old favorite foods may be tempting, but know that not adhering to diet instructions from your weight loss physician increases your risk of complications during surgery. A fatty liver makes weight loss surgery more dangerous. Stay safe by steering clear of these foods.

  • Foods high in carbohydrates and starches. Bread, pasta, potatoes, pizza, cereal and rice should also be avoided.
  • Foods high in sugar. Besides chocolatey desserts, cakes, cookies and the like, do not allow sugary fruit drinks to enter your liquid diet. You should not only avoid packaged fruit drinks, but avoid the appeal of juicing fruit, since this can cause your daily caloric intake to increase quickly because of the amount of fruits you need for a small serving of juice.
  • Foods high in fat. Cheese, fried foods and fatty meats are all high in fat and calories and can wreak havoc on your digestive system.

If you’re used to eating these types of foods, you may face some mental difficulties when you begin your pre-op diet. The good news is, these decrease over time, and feel-good effects will start to supplant any hunger or cravings you have. As your body starts to burn more body fat for energy rather than high-calorie sugar and carbs, those cravings will also decrease. A study of the effects of a high-protein diet found that swapping protein calories for sugar/fat/carb calories increases satiety and appetite control, which contributes to more effective long-term weight loss.

Create a meal plan with your physician

Pre-Op Guide: What to Eat Before Weight Loss Surgery

Your physician is available to answer any questions you have and provide tips to help reduce cravings. These 25 healthy alternatives to snacking are a great place to get inspiration. And remember, if you veer off your pre-op diet plan, it’s vital you are transparent with your doctor. This helps ensure the safest surgery possible. 

Know that every healthy nutrition decision you make before your bariatric surgery is increasing your likelihood of having the most amazing weight loss results possible. By making healthy choices and following doctor’s orders early on, you’ll be more likely to have a successful surgery and the weight loss results you desire. 

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