Is the Gastric Sleeve Surgery Pre-Op Diet Really That Bad?


Yes. Or no. Does that help? The truth is that I’ve heard the gastric sleeve pre-op diet described as everything from “horrible” to “a breeze”. Your experience will be your own, though some things tend to be pretty common during this period. But first, let’s take a quick look at a few pre-op diet facts.

When you’re preparing for gastric sleeve surgery at Endobariatric’s Mexico hospital, you’ll likely be put on a pre-op diet prior to the procedure. Lasting anywhere from seven to 21 days, depending on your BMI, the pre-op diet isn’t intended to “accustom” you to a life of deprivation following your VSG. Nor is it designed as a weight-loss regimen, though most patients do lose some weight. It’s prescribed because of a condition called fatty liver, which afflicts most obese people. With fatty liver, the organ is enlarged and heavier, making vertical sleeve gastrectomy risky on a number of levels. The goal of the pre-op plan is to shrink the liver so that the surgery will be as safe and effective as possible.

The pre-op diet, whose daily calorie goal is about 1,000, is highly regimented, meaning that we give you detailed lists of foods and beverages to consume, as well as recipes to help you plan meals and snacks. So what can you expect? Read on for some fairly universal challenges and how to address them. 

Challenge #1: “I don’t feel great.”
Headaches, in particular, pop up often for pre-op dieters, especially in the first several days. These tend to be dull aches by the way—not migraines or anything debilitating. Two common reasons for this is a decrease in your caffeine and/or sugar (carbs) intake. You can still have coffee and tea on the plan, but some people cut back on their usual caffeine sources to make more “stomach room” for foods and liquids with calories. Cutting way back on sugar and carbs, whether before surgery or after, is a prime way to bring on withdrawal headaches as the body detoxes from them. Better to get it out of the way now! If aspirin doesn’t work, our own Brandi Carter recommends Midol, which has helped many fellow patients eliminate the pounding. Lots of water can help, too.

Another snag may be a bit of joint pain. Some VSG patients experience these joint and muscle aches as tissues start to shift and support your weight differently. Though more typical once you’ve lost a larger number of pounds, it can start in the pre-op phase.

Challenge #2: “I’m not getting enough calories/I’m bored with the food.”
Struggling to ingest enough calories may seem like an impossibility if you’re used to drowning in them. But when the foods you’re prescribed contain very few calories, it can, indeed, be a problem. Protein shakes tend to be the most calorie-dense options on the plan, but some people simply don’t like them. Try as many brands as possible, as well as flavorless protein supplements (Genepro makes one) that can be mixed into just about anything you do like. Generally, if you can get in the recommended amount of protein, you’ll hit your calorie goal, too. My best advice, though, is to simply do your best. The calorie range you’re given is a goal—not something to stress over.

As for the boredom issue, I get it. There’s a long list of options, but things can get tedious after a while. Remember that you’re given a lot of freedom with non-starchy vegetables. In addition to eating them raw or in a soup, you can bake, roast, grill, sauté with broth, etc. Switch up your technique and the veggies themselves to help keep things interesting.

Challenge #3: I haven’t lost weight—and I haven’t cheated!
It can be discouraging for patients to follow the pre-op plan to the letter and then lose only a pound or two before the VSG procedure. Some people believe this indicates that vertical sleeve gastrectomy won’t work for them or that I’ll question their honesty. Neither is true. As I mentioned above, the pre-op diet is not about losing weight; it’s about getting your liver in tip-top shape. There are a number of reasons the scale doesn’t move during this period, including the fact that your body might be “shocked” into holding onto the weight. Blame evolution. After surgery is a whole other ballgame, and the pounds will come off. As my patient, Amy, advises: “Keep the faith. I didn’t really lose much weight on the pre-op diet, but after surgery I did.”

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“Changing lives…one sleeve at a time”.