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How Does Gastric Sleeve Surgery Impact Your Metabolism?

Posted on 08 Jun, 2023
How Does Gastric Sleeve Surgery Impact Your Metabolism?

There are many common misconceptions about gastric sleeve surgery out there. Many people think it’s simply a surgery to make your stomach smaller, which results in you eating less food and therefore losing weight in the process. While, of course, there’s some truth to this, it doesn’t tell the full story.

Let’s make it clear - 80% of your stomach is removed during the surgery, and this reduction is a major contributor to weight loss. However, the weight loss you achieve post-surgery is not solely because you now have a smaller appetite and you’re consuming fewer calories.

Weight loss is massively affected by your metabolism, which is very difficult to influence or manipulate yourself. However, gastric sleeve surgery has changed the game. A sleeve gastrectomy causes a combination of changes to occur to your metabolism, which makes it a lot easier consistently lose weight for years to come.

In this article, we’ll answer the common questions: ‘Does gastric sleeve change your metabolism?’ and ‘How do I increase metabolism after gastric sleeve?’ We’ll delve deeper into the weight loss journey after a sleeve gastrectomy and explain how these metabolic changes play a fundamental role. Let’s get into it.

How Does Gastric Sleeve Surgery Work? 

Gastric sleeve surgery (also known as sleeve gastrectomy) is Australia's most common bariatric procedure, with thousands of Australians opting for the procedure every year. Gastric sleeve surgery is popular for a reason: long-term sustainable weight loss.

A gastric sleeve surgery involves removing 80% of the stomach to leave a much smaller banana-shaped ‘sleeve’. With such a reduction in stomach size, people who undergo this procedure can hold much less food than they could pre-surgery.

Firstly, this massive physical reduction in the size of the stomach greatly helps with appetite control and food consumption. However, there is a lot more that happens. This combines with intricate hormonal changes within the body and a significant increase in metabolism to help facilitate incredible short-term, and long-term weight loss.

Gastric Sleeve Surgery – More Than Just a Smaller Stomach

Time and time again - it has been proven that simply cutting calories and reducing your food intake does not produce long-term weight loss. Yes, people can instantly drop a few kilos by significantly reducing their caloric intake, but let’s be real - it’s not a healthy (or sustainable) to maintain a lower body weight.

Without changes to metabolism, people who focus solely on calorie restriction alone and aggressive dieting will initially lose weight, but then within 18-24 months, will revert to their old weight - or even sometimes much heavier than they once were! This is why gastric sleeve surgery is so effective – it is about much more than just reducing the size of your stomach (and how much food it can hold!)

With gastric sleeve surgery, there are different mechanisms that come into play with your metabolism, which help to achieve long-lasting, healthier weight loss. At Central Coast Surgery, we have seen firsthand patients experiencing weight loss and healthy weight maintenance lasting more than 20 years. We love to see people changing their lives in this way, and it is largely due to the effects the gastric sleeve surgery has on their metabolism and the various hormonal shifts that happen post-surgery.


fact about gastric sleeve surgery


What Role Does Metabolism Play in Weight Loss?

In very simple terms, your metabolism converts the food you eat into energy. In all of our bodies is a delicate energy balance. Your metabolism helps to regulate this balance and plays a fundamental role in achieving and maintaining a healthy body weight.

You’ve probably heard friends boast and brag about their ‘fast metabolism’ before. These lucky people can eat all the delicious treats that they want without packing on any unwanted pounds. However, it would be a lot more accurate to describe it as an ‘efficient’ metabolism, rather than a fast metabolism. An efficient metabolism is highly productive at taking the food you consume and converting it to energy.

Unfortunately, we do not all naturally have an efficient metabolism, particularly as we age. The sad reality is that an inefficient metabolism will make it a lot more difficult to lose weight. But don't worry, it’s not all doom and gloom. There are ways to influence the efficiency of your metabolism, and when you do, you will see phenomenal results in your weight loss journey.

Does Gastric Sleeve Surgery Change Your Metabolism? 

Gastric sleeve surgery affects the metabolism in profound ways, with immense weight loss benefits, including the following:

  • Improving fat storage metabolism

  • Lowering your blood sugar

  • Increasing your metabolic rate.

These complex changes and the effects on your metabolism are caused by modifications in the hormonal landscape in your gut and the composition of gut bacteria. 

Changes in Bile Acids and FXR Receptors

Bile acids are essential for fat digestion and metabolising food. A sleeve gastrectomy will increase the bile acid level within your stomach, leading to greater fat metabolism. The surgery will also augment the sensitivity of the Farnesoid X Receptor (FXR), which regulates bile acid production. As a result, bariatric surgery affects your metabolism in a positive way and facilitates further weight loss. 

The Role of Gut Bacteria in Weight Loss

Another factor contributing to the success of gastric sleeve surgery for weight loss is the impact of the procedure on the gut microbiome. After the surgery, the new and improved gut environment favours certain types of bacteria. The gut bacteria help break down dietary fibre and produce short-chain fatty acids, which regulate your appetite and boost metabolism. 

The Role of Hormones in Regulating Your Metabolism

The effects of gastric sleeve surgery in terms of influencing your metabolism and losing weight are mainly due to the regulation and impact on the hormones produced in your stomach and intestines.

A sleeve gastrectomy will create long-lasting changes in the balance of your hormones that govern hunger levels, satiety, and metabolism. Combining the physical changes to your stomach with these intricate hormonal changes can help you to achieve long-term metabolic regulation and weight control. 

In a gastric sleeve surgery, the outer portion of your stomach is removed. Only by altering the actual stomach tissue (where the hormones come from) through this type of surgery will create lasting changes to your hormones and how they are regulated. With this regulation comes the long-term sustainable weight loss that people strive for.  


hormones impacting metabolism


The Role of Hormones in Regulating Your Metabolism

Your hormones act as chemical messengers to your body, crucial in managing your hunger and fullness, metabolism, blood glucose levels, and how your body will store energy as fat. Thus, if you can manipulate these hormones in your favour, you have much greater potential for weight loss. 

Gastric sleeve surgery dramatically changes your hormones, facilitating significant weight loss and metabolic improvements. 


Often referred to as the 'hunger hormone', your ghrelin levels will drop after a sleeve gastrectomy, leaving you feeling much less hungry all of the time and therefore eating less food.


Insulin regulates your metabolism and controls your body’s glucose levels. After gastric sleeve surgery, your body will be a lot more effective at maintaining normal blood glucose levels.


Produced by the fat cells in your body, leptin is a powerful hormone that naturally suppresses your appetite. Post-surgery, your leptin levels will quite quickly reach optimal levels, and therefore, help you to manage fat storage and minimise your midnight cravings.

How to Increase Metabolism After Gastric Sleeve with Central Coast Surgery

Gastric sleeve surgery offers a unique opportunity to achieve long-term sustainable and healthy weight loss. A sleeve gastrectomy is much more than a quick fix. As well as reducing the size of your stomach and consequently the amount of food you consume, the surgery profoundly impacts your metabolism and hormones.

Removing 80% of your stomach, the resulting intricate impact on your hormones influences your hunger, satiety, metabolism, and overall, how your body and brain interact with food. Gastric sleeve surgery helps you create a better relationship with food and improve your metabolism's efficiency. Mentally, you will develop better habits, and physically your body will more productively transform food into energy rather than storing it as fat.

At Central Coast Surgery, we have seen gastric sleeve surgery transform people’s lives. If you’re struggling with weight loss and don’t know where to begin, reach out to our team and embrace this incredible opportunity.