Your doctor has mentioned Ozempic, Wegovy or Mounjaro. You have read that the weight comes off without effort and that hunger disappears. That is partly true. But one question often goes unanswered: what should you eat when you are no longer hungry?
The medication works on your appetite. It does not choose what ends up on your plate. And what is on your plate matters: it decides whether you keep your muscle, whether you tolerate the treatment well, and whether the weight stays off the day you stop.
In this article, you will find out what the medication does, what it does not do, and how a dietitian helps you get the most from it, without hunger and with meals you enjoy.
Our promise at Diaeta: meals without hunger, made from foods you find tasty. Your doctor prescribes and monitors your treatment. We take care of your eating, in contact with your doctor.
1. The Essentials in 30 Seconds
- The great results you have read about come from patients who were supported. In the large studies, every participant received regular guidance on eating.
- Many patients stop in the first year, often because of nausea or constipation. Eating in a way that suits your body helps you get past this stage.
- You eat less, so you risk falling short on protein, fiber and vitamins. About one person in five is diagnosed with a deficiency within the year.
- Part of the weight you lose comes from muscle. Enough protein and a little strength training limit this loss.
- When you stop, hunger comes back. The habits you build during treatment help you keep your results.
2. The Impressive Results Come with a Catch
You may have heard about losing 15 or 20% of body weight. Those figures are real. They come from the large studies that led to these medications being approved.
One detail often goes unnoticed: in those studies, nobody received the medication alone. Every participant had regular follow-up with advice on eating and physical activity. In some studies, they met a professional every two or three weeks for more than a year.
Health authorities also approved these medications as an addition to suitable eating habits and physical activity. The medication does a big part of the work. Your meals do the rest.
3. The First Weeks: When Many People Give Up
Nausea, bloating, diarrhea, constipation: between a third and a half of patients feel these effects, mostly in the first weeks and with each dose increase. They often fade with time. But some patients do not make it that far.
In real life, between one patient in five and one in two stops treatment within the year, depending on the study. Digestive effects are among the main reasons. Patients who keep going get results close to those of the large studies.
Good news: your plate can do a lot for your comfort. Specialists recommend adjusting what you eat before even turning to anti-nausea medication:
- small portions, several times a day;
- less fried food and very fatty dishes;
- eat slowly and stop as soon as you feel full;
- raise your water and fiber intake little by little to ease constipation.
A dietitian turns these principles into real meals that you like and your stomach accepts. You will find ideas in our guide what to eat on Ozempic, Wegovy or Mounjaro.
Important: if you vomit for several days in a row, if you can no longer drink, or if you have severe abdominal pain, contact your doctor right away.
4. Less Appetite, but Enough Nutrients?
On treatment, you may eat up to 40% less. Your portions shrink, and so does your intake of protein, fiber, vitamins and minerals.
Studies confirm this risk. About one person in five is diagnosed with a deficiency in the year after starting treatment. Vitamin D comes first, followed by iron and B vitamins. Fiber intake often stays too low, which does not help constipation.
The goal is not to eat more. The goal is for every small plate to truly nourish you. A dietitian reviews what you eat, spots what is missing and suggests simple foods to fill the gap. If a blood test or a supplement seems useful, the dietitian discusses it with your doctor.
5. Losing Fat, Keeping Your Muscle
When you lose weight, you mostly lose fat, but also a little muscle. With these medications, about a quarter to a third of the weight lost comes from this "lean mass". That is comparable to weight loss without medication.
Your muscles matter: they keep you strong, mobile and independent, especially as you age. Two things protect them:
- enough protein, spread over the day, even when your appetite is small;
- a little strength training, suited to your fitness level. In studies, it cuts the amount of muscle lost by about a third.
A dietitian calculates your protein needs and turns them into meals you can actually finish. A body composition analysis checks that you are losing fat and not muscle. To go further, read our article on muscle on Ozempic and Mounjaro.
6. The Day You Stop
These medications calm hunger as long as you take them. When you stop, your appetite returns. Studies show that one year after stopping, patients had regained on average about two thirds of the weight they lost.
This regain is not inevitable. People who move regularly during treatment keep their results better after stopping. The eating habits you build while your appetite is quiet are the ones that protect you when it comes back.
A dietitian helps you prepare for this stage from the start, then adjusts your meals when hunger resurfaces. Our article stopping Ozempic or Wegovy without regaining weight lays out this plan in detail.
7. What Does a Dietitian Actually Do?
Nutrition and obesity societies, in Europe and in the United States, recommend nutritional support during these treatments. Here is what it looks like, step by step.
Before the first injection
- We review your habits, your tastes, your other health conditions and your goals.
- We measure your starting body composition: fat, muscle, water.
- We check your relationship with food, so we can support you as well as possible.
During the first weeks
- Together, we put together small meals that you digest well.
- We prepare solutions for days with nausea or constipation.
- We set your targets for protein, fiber and water.
During treatment
- We track your body composition to protect your muscle.
- We watch your vitamin and mineral intake, in contact with your doctor's blood tests.
- We adjust your plan with each change in dose and appetite.
Before and after you stop
- We build a plan for when your appetite returns, using foods you love.
- We stay by your side during the following months, the period when weight comes back fastest.
8. In Belgium
In Belgium, Wegovy and Mounjaro are not reimbursed for weight loss. In October 2026, the health minister refused to reimburse Mounjaro. He judged that large-scale reimbursement, without multidisciplinary support around the medication, would be irresponsible. Ozempic and Mounjaro remain reimbursed for type 2 diabetes, with prior approval from your health insurance fund.
If you pay for your treatment yourself, support helps you get the most from that investment. Several health insurance funds reimburse part of the consultations with an INAMI registered dietitian: check with yours.
9. Your Questions
The medication cuts my hunger. Do I really need a dietitian?
The medication reduces how much you eat. It does not guarantee that you eat enough protein, fiber or vitamins. A dietitian helps you eat well with a smaller appetite, and keep good habits for afterward.
When should I start?
The best time is before the first injection. You can also start along the way, for example if nausea is getting in your way or if you are thinking about stopping.
Can the dietitian change my treatment?
No. Your doctor prescribes and decides the dose. The dietitian takes care of your eating and tells your doctor if something is a concern, such as lasting digestive problems or muscle loss.
Does a dietitian guarantee better results?
Nobody can guarantee a result. Studies have not yet directly compared these medications with and without a dietitian. But every major published success included nutritional follow-up, and specialist recommendations all point the same way.
I take Ozempic for my diabetes. Is this useful for me too?
Yes. Nutritional follow-up improves blood sugar, weight and blood pressure in people with prediabetes or diabetes. Also see our diabetes page.
Are the consultations reimbursed?
Several health insurance funds reimburse part of the consultations with an INAMI registered dietitian. Amounts vary: check with yours.
10. Our Approach at Diaeta
In Brussels, we support people on Ozempic, Wegovy or Mounjaro, from the first month through to maintenance. We work in contact with your doctor.
What We Promise You
- Never hungry: filling meals, suited to the appetite your treatment leaves you.
- Foods you love: your favorite dishes stay on the menu, in adjusted portions.
- Science-based advice, updated with the latest recommendations.
- A plan that evolves with each dose, each change in appetite and the end of treatment.
Discover our GLP-1 support and our weight loss support.
Has your doctor suggested Ozempic, Wegovy or Mounjaro, or have you already started? Book an appointment for a personalized consultation in Brussels.
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