Why Weight Loss Sometimes Stalls
It’s completely normal to experience periods where weight loss slows down after gastric sleeve surgery. These “plateaus” can feel frustrating, but they usually have clear explanations. Often, the issue is that eating habits haven’t fully adjusted to the new digestive system. Proper nutritional guidance before and after surgery helps set realistic expectations and prepares you for these phases. If your weight loss isn’t progressing as expected, one or more of the following reasons may be involved.
1. You’re Not Eating Enough Calories
It may sound surprising, but eating too few calories can halt weight loss. After surgery, levels of the hunger hormone ghrelin drop sharply, so you often don’t feel hungry. Combined with a much smaller stomach — reduced from the size of a football to the size of a thumb — many patients unintentionally eat far too little.
When the body receives too few nutrients, it starts breaking down muscle along with fat. The less muscle you have, the slower your metabolism becomes, making further weight loss more difficult. This leads to the well-known plateaus.
How much you should eat depends on how long it has been since surgery. During the first four weeks, calories are not the priority. Once you transition to more normal foods, aim for 800 kcal, eventually increasing to 1000–1200 kcal per day. Eating less than this slows weight loss in the long term.
2. Your Diet Is Unbalanced
Once you’re at least four weeks post-surgery, it’s important to include solid protein sources and healthy fats. Protein needs can be estimated using your ideal body weight.
Example: A person who is 1.70 m tall has an ideal weight of around 70 kg, which equals roughly 70 g of protein per day.
This is the minimum. For continued weight loss, a higher protein intake is often necessary.
Your macronutrient ratio also matters. Instead of aiming for exact grams, focus on balanced proportions:
- 10–35% carbohydrates
- 30–40% fat
- 35–50% protein
Also ensure that daily sugar intake stays below 25% of total calories.
3. You’re Eating Too Many “Soft” Foods
Some people struggle to return to solid foods after surgery. They may feel that poultry or other protein-rich foods “don’t go down well.” Over time, this can lead to avoidance of solid proteins and reliance on foods that “slide down easily,” such as yogurt, mashed potatoes, creamy soups, or even ice cream.
The problem: these foods lack structure, contain fewer nutrients, and often cause hunger to return quickly. They also tend to be high in simple carbohydrates, which slows progress. Reviewing your eating habits often reveals whether “soft foods” are taking up too much of your diet.
4. You’re Exercising Too Much, Too Soon
It’s natural to feel motivated after surgery and want to accelerate weight loss with intense exercise. But doing too much too early, especially while eating too little, slows weight loss instead of speeding it up.
Walking outdoors is excellent and recommended from the start. However, anything more strenuous should wait until all surgical wounds are healed — usually 6–8 weeks post-surgery.
You should also be able to comfortably eat 800–1200 calories before beginning structured workouts.
5. You’re Not Exercising at All
While nutrition plays the biggest role (around 80% of success), exercise still contributes the remaining 20% — and it matters. Building lean muscle mass increases your metabolism, helping the body burn calories more efficiently.
Once you’ve passed the 6–8 week mark and your diet is balanced, a structured endurance training routine can significantly boost fat loss. If you’re unsure where to begin, seek guidance from a trainer, gym, or sports club. Most workouts can even be done at home.
Be Patient — Your Body Needs Time
Weight gain didn’t happen overnight, and weight loss won’t disappear instantly either. Temporary stalls are normal. Weighing yourself too often can make progress seem slower than it actually is. Give your body time — usually a few weeks — to adjust and continue burning fat.
Everyone is different. General recommendations can guide you, but your unique needs determine how fast you lose weight. Avoid comparing yourself with others; genetics, metabolism, and lifestyle all play major roles.
If you’re consistently following the guidelines but still not losing weight, discuss it with your dietitian. In some cases, the chosen surgical method may not be the most effective for your individual situation.
