The past year has completely changed the way we view obesity. Whereas in the past we were told it was just a matter of "willpower" or "fewer calories," today the medical world understands that it is a chronic biological disease that requires long-term medical treatment.
By the end of 2025, the World Health Organization (WHO) even issued new guidelines recommending slimming injections as a central tool for improving health globally—not for appearance, of course, but to save lives and prevent heart disease.
However, I have a few important “buts” for anyone considering their use. Before that, let’s understand:
How the injections work
The new injections do not "burn fat"; they change the hormonal communication in our bodies. Inside the body, there are hormones called “incretins” that are secreted from the gut when we eat.
The main hormone, called GLP-1, does three main things: It signals the pancreas to release insulin, it slows stomach emptying so we feel full longer, and most importantly – it sends a signal to the brain that says “we are full.”
The new medications penetrate the brain and seemingly silence what is called “food noise” – the constant thoughts about the next meal.
The new generation of drugs activates both GLP-1 and another hormone called GIP. This combination makes the process much more effective and reduces some of the side effects.
How much weight do you really lose? (2025–2026 data)
The numbers range between 5–20%, depending on the drug, the dose, and of course the individual and starting weight. 5% is not much and is insufficient in most cases; 20% is a high result. But – note that there is a gap between studies and reality: In real life, people lose less, mainly because it is difficult to maintain due to side effects or supply interruptions.
Success in the process is not only measured by weight. Studies from the past year show significant improvement in blood pressure, blood sugar, and blood lipids. Those who reach the highest doses and maintain consistent treatment see the best results. Today, there is an additional emphasis: Close nutritional and medical guidance is an integral part of treatment success.
For Dr. Maya Rosman’s online diet course, click here.
Side effects: What price does the body pay?
Almost everyone using the injections experiences side effects, mainly involving the digestive system. Some include:
1. Nausea, vomiting, diarrhea, or constipation. The most common (about 21%).
2. “Stuck stomach” (Gastroparesis): The drug slows the stomach so much that in some people the food stays there too long. This can cause severe vomiting and even pose a risk during surgery (as the stomach is not empty even after fasting).
3. Gallstones: Losing weight too quickly can cause gallbladder problems.
4. Eye problems: In diabetic patients, semaglutide can temporarily worsen retinal damage.
5. Muscle loss (the silent danger): Probably one of the biggest downsides. About 25% to 40% of the weight lost is muscle rather than fat, which can leave the body weaker and more vulnerable, especially in older adults.
What happens when you stop the injection?
New studies from January 2026 clearly state: For most people, stopping the injection means regaining weight. Our bodies "fight" to return to the higher weight they were used to.
Data shows that once stopped, weight returns at almost half a kilo per month, and within less than two years most people return to their starting point. When the injection is stopped, hunger returns strongly, the stomach empties faster, and the brain demands food again. The only way to maintain results is to combine strength training and proper nutrition during treatment.
You may have seen ads claiming you can "eat everything and still lose weight." We know this isn’t true and it’s a very strong marketing message. But when it comes to these injections, it works for a few reasons:
Marketers claim that because the injection silences “food noise,” a person can eat one slice of pizza and stop there without feeling compelled to devour the whole tray.
There is also the physical barrier: The stomach is simply too full. It’s physically impossible to consume large amounts of carbohydrates.
After all this, of course, there is the promise of magic: People are tired of strict diets and are looking for a solution where they don’t have to give up the foods they love. The wet dream.
But here’s a dangerous trap: When eating much less but continuing to eat “bad food,” the body enters a state of malnutrition. Studies warn that injection users suffer from severe deficiencies in vitamins and minerals (like vitamin D, magnesium, and zinc) and dietary fiber. This can damage the immune system and bones.
Notable downsides to know
1. Loss of strength and muscle: One of the most common side effects among people who don’t improve their diet quality. The body may become “thin but weak,” increasing the risk of falls and fractures in older adults.
2. High cost: Treatment is very expensive (sometimes over NIS 1,000 per month without subsidies), causing many to stop midway.
3. Lifetime dependence: Ultimately, for long-term results, injections may be needed weekly, perhaps forever – a significant burden.
4. Processed food remains: The injection does not teach healthy eating. And this is the worst thing. If sugar and salt continue to be consumed (even in small amounts), the biological addiction does not disappear.
<br>Who benefits most from using injections?
Recent studies show that injections are “life-saving” for certain groups:
Fatty liver patients: Dramatic improvement in liver condition.
Women with polycystic ovary syndrome (PCOS): Helps balance hormones and improve fertility.
Sleep apnea patients: Weight loss eases nighttime breathing.
Heart patients: Proven reduction in risk of heart attack and stroke.
Diabetes patients: Sugar control and kidney protection.
The perception in 2026 is that to succeed, the injection must be accompanied by a “supportive diet.” Alone, it is not really a solution. Attention must be paid to:
1. Plenty of protein: To protect muscles (eggs, fish, chicken, legumes).
2. Plenty of water and fiber: To prevent severe constipation.
3. Nutritional supplements: To compensate for what is lacking due to low food intake.
<br>In conclusion
Slimming injections are a remarkable medical breakthrough, but they are not a “quick fix.” They help our biology and silence hunger in the brain, but the price is digestive side effects and the risk of muscle loss.
The message that “you can keep eating junk food” is a dangerous mistake that can lead to malnutrition. Ultimately, the injection is only a “scaffold.” To build a truly healthy body, you must combine strength training, eat protein, and understand that this is likely a long-term treatment, not a temporary solution.