Is a ketogenic diet after gastric sleeve surgery a good idea? To answer that question, let's first look at what gastric sleeve surgery is. Gastric sleeve surgery, also known as a sleeve gastrectomy, is a type of surgery that can assist in weight loss by restricting food intake.

It does this by reducing the volume of the stomach by about 75 %. After this type of weight loss surgery, a person’s diet can change dramatically. Not only will certain foods be less tolerated, but you will also tolerate much smaller portions.

Before surgery, some insurance companies will require a person to lose a certain amount of weight before a person receives approval for surgery. Therefore, some people adopt low-carbohydrate regimens to assist in such weight loss. One such extreme form of low-carbohydrate diet is the ketogenic diet.

Read below for more information on the ketogenic diet. Also, learn about the pros and cons of this diet for those pre- or post-gastric sleeve surgery.

What Is the Ketogenic Diet?

The ketogenic diet is an extreme form of the low-carbohydrate diet that is also high-fat. This type of diet was originally made for those with seizure disorder. However, since it also produced some weight loss, people started using it for weight loss purposes.

The ketogenic diet restricts carbohydrates to a point where the body enters a state of ketosis. This state of ketosis turns the body’s fuel source from carbohydrates to fat. By doing this, it can assist in fat burning.

The ketogenic diet only allows about 5 to 10 % of calories from carbohydrates. It also calls for consuming 70 % of calories from fats and about 25 % of calories from protein.

Does the Ketogenic Diet Help with Weight Loss?

Research shows that the ketogenic diet can help a person lose weight up to one year after starting the regimen. However, more long-term studies need to confirm such results before it’s recommended as a safe and effective weight loss method.

Can the Ketogenic Diet Help Those Getting Gastric Sleeve Surgery?

Research shows that following a very low-calorie ketogenic diet (VLCKD) a few weeks prior to bariatric surgery is both effective and safe. And it’s safe for those morbidly obese both with and without type 2 diabetes.

Can the Ketogenic Diet Help Lose Weight after Gastric Sleeve Surgery?

Although it may be safe and effective for before surgery, the ketogenic diet after gastric sleeve surgery might not be suitable. This is because after gastric sleeve surgery, you will not tolerate fats well. Therefore, if you consume a high-fat diet like the ketogenic diet after gastric sleeve surgery, it could cause painful gastrointestinal (GI) symptoms.

Also, experts suggest that a high-fat diet could increase risk of heart and kidney disease over time. Not to mention,  if you stop the ketogenic diet after surgery, you could regain weight lost on this regimen.

So What Diet Should You Follow after Gastric Sleeve Surgery?

To avoid yo-yo dieting after surgery, it may be best to stick with a more sustainable diet after surgery than the ketogenic diet. Research shows that the most common amounts of macronutrients people consume post-bariatric surgery include:

• 35 to 48% calories from carbohydrates
• 37 to 42% calories from fat
• 1.1-1.5 grams protein per kilogram of body weight of protein

Protein intake will be extremely important after gastric sleeve surgery to assist with maintaining muscle tissue. Therefore, at a minimum you should consume around 65 to 75 grams of protein daily after gastric sleeve surgery. High-protein foods include eggs, meat, poultry, fish, seafood, tofu and dairy products like yogurt and cottage cheese.

It may be hard to meet the minimum protein needs in the first few months after surgery since you will be eating smaller portions. Therefore, just try to consume as much protein as you can at mealtimes. Consume frequent meals every few hours to maximize protein intake daily. You may have to supplement some meals with protein shakes to help meet daily protein needs.

What Are Some Tips to Help Make Sure I Meet My Daily Macronutrient Needs?

You will have a lot of information to remember after surgery to help you heal and achieve optimal post-surgical outcomes. Therefore, to make the nutrition part of your post-surgical journey easier, it will benefit you to track your food.

There are many food tracking applications on your smartphone or computer that can help you do this. These apps can help you track how many macronutrients you are eating each day as well as track water intake.

Other tips to help you stay on track with your post-surgical diet include:

• Find an hour each week to plan meals and snacks that meet your dietary needs.
• Make a grocery list of food you will need for planned meals and snacks.
• When you run out of a certain food item, make sure to add it to a running grocery list so you will have it on hand to continue eating healthy.
• Take 15 minutes after dinner each night to prep meals and snacks for the next day. This can prevent you from getting off track and grabbing unhealthy convenience food options.

Take Home Message

Gastric sleeve is a life-changing procedure that can help people lose weight and lower their disease risk. However, to have the opportunity to receive this surgery, patients may need to lose some weight before surgery. Research shows that a ketogenic diet may help achieve this pre-surgical weight loss.

It’s important to note, though, that such a high-fat diet may not be suitable for after gastric sleeve surgery. This is because you will not be able to tolerate fatty foods after surgery. These types of foods can cause GI distress.

However, a person who followed a ketogenic diet prior to surgery can still consume a low-carbohydrate diet after surgery if they choose. They will just have to avoid fatty foods to lessen the risk for painful side effects.