Hunger after sleeve gastrectomy can feel surprising or frustrating to patients, especially since one of the surgery’s main goals is to reduce appetite. The return of hunger can create a challenging environment due to the imbalance of ongoing restriction versus an insatiable appetite. It is an unusual phenomenon which can vary amongst patients depending on multiple factors. For some, the sensation of hunger can return rather quickly after surgery while for others, it may remain under control for years to come.
In this blog we explore the complex physiological, psychological, and behavioural reasons on why this may be happening to you.
Hormonal Adaptation
The main goal of sleeve gastrectomy is to be able to remove approximately 70-75% of the stomach. As part of resection, most, if not all, of the stomach fundus (top part of the stomach) is removed and this is also the area which involves the production of Ghrelin – more commonly known as the dominant hunger hormone.
This is one of the main reasons for why you may not feel hungry after bariatric surgery. This post surgery phase is often referred to as the “honeymoon phase” where food craving is reduced to a bare minimum. In some individuals, this phase may last for years although others may experience a return of hunger within 6 to 12 months following surgery. In the instance where hunger is present immediately after surgery along with a lack of restriction, one must ask the question of whether enough stomach was removed during surgery, particularly the stomach fundus.
We now know that the body is never as simplistic as what we thought it to be with hunger hormones returning over time because of physiological adaptation. This is akin to natural eco-systems where if we remove the apex predator, evolution while allow others to slowly take its place with a return to equilibrium.
Ghrelin levels may gradually return as it is a hormone which is also produced in smaller quantities by other parts of the gastro-intestinal tract. Furthermore, other hormones like leptin and GLP-1, which plays a role in reducing hunger, may down regulate their effect to help counter-balance the loss of effect from Ghrelin.
Mistaking Other Sensations for Hunger
After surgery, traditional “stomach growling” hunger may feel different. You may notice an increase in noise from the upper abdomen which can be very different to what you had experienced prior to surgery. Sometimes, these sensations can be confused with hunger but are actually caused by acid/ bile irritation, dehydration or previously established emotional eating cues.
This is one of the main reasons for why staying hydrated after bariatric surgery is crucial in managing perceived “hunger signals” and one of the key principles following surgery.
Stomach Compliance Increases Over Time
A common misunderstanding is that the sleeve would stretch over time. Even though conceptually this may be true, it is indeed the stomach being more compliant rather than the stomach physically enlarging over time. This is evident in follow up scopes which would often show that the stomach shape and size remain rather similar to when the sleeve was originally fashioned. As the linings of the stomach softens, portions sizes can increase although for any one sitting, it should still remain well below what you can eat prior to surgery.
Eating quickly or drinking while eating can hasten the process of reduced stomach compliance. A similar concept is when we fill a balloon with fluid and find it easier to stretch (i.e. more compliant) once we pass the point of resistance. With time, this process will inherently “train” the stomach to be able to hold down more. Our perceived sense of fullness/ hunger will also adapt according to our habits.
Food Choices and Satiety
Of all the points, this one is probably the most important. Making the right food choices can significantly impact your weight loss and hunger levels. Undergoing bariatric surgery is a life-long commitment and part of the process is about slowly chipping away at in-grained dietary habits. We must understand that not all foods trigger the same feeling of fullness:
- Soft or liquid calories (ice cream, soups, smoothies, alcohol), also known as “slider foods” pass quickly and do not elicit the same satiety signals as more wholesome food groups.
- Highly processed or refined carbs can lead to spikes in blood sugar, followed by violent drops because of sudden insulin rises. This is also the cause of delayed dumping which can then subsequently results in reactive hunger.
- Protein and fibre-rich foods should be prioritised as you have limited stomach space and these food groups also promote satiety, while slowing digestion.
Dietitians often advise: “Focus on lean protein first at every meal. That keeps you fuller for longer and stabilises hunger.”
Patients do best when they are able to work closely with dietitians in tweaking their diet. Understanding dietary principles following bariatric surgery is crucial for sustainable weight loss results.
Psychological & Emotional Factors
Our relationship with food can often be complex with deep roots in existing habits and psychology. Emotional hunger is a real phenomenon which can persist after surgery if the root causes are not adequately addressed. This can include our unhealthy connections to food in times of stress and trauma. Just like any form of addiction, patients who have used food to soothe emotions, can revert to previous habits post-surgery when triggers remain. In these situations, it’s not exactly physiological hunger but rather, emotional hunger that drives cravings.
When recommended, patients with emotional eating habits should seek psychological support before embarking on your bariatric journey.
How to Manage Hunger?
Here are several key concepts to grasp to help you get onto of hunger signals:
- Track hunger patterns – true physical hunger vs head hunger
- Prioritise protein, fibre, water at meals
- Eat at regular time intervals and make a conscious effort not to miss meals
- Avoid grazing and slider foods (e.g. chips, sweets)
- Eat mindfully & slowly to give satiety cues time to work
- Follow up with your specialist bariatric team to trouble shoot
- Keep an open mind to bariatric management – in select cases, some patients may benefit from adjunct therapies such as GLP-1 medications under medical supervision. Outcomes vary, and consulting with a licensed bariatric specialist ensures that any treatment is tailored and safe.
