What to Eat on GLP-1: Wegovy, Ozempic and Mounjaro

If you have started on Wegovy, Ozempic, Mounjaro or Saxenda, you have probably noticed the food noise go quiet. Meals you used to finish, you cannot. Food you used to think about, you do not. That is the medicine working - and it is the easy part.

The harder part is what to eat on GLP-1 once your appetite has dropped. Eating well on a small appetite is a skill. Eat too little and you lose muscle along with the fat and fall short on nutrients; build no new habits, and the weight comes back when the medicine stops.

Why eating well gets harder, not easier

These medicines copy a hormone your gut releases after you eat, so you feel full sooner, stay full longer, and food leaves your stomach more slowly. Eating less is no longer the challenge. The challenge is that every bite now has to carry more - and most people are prescribed these medicines without ever meeting a dietitian.

Eat regularly, even when you are not hungry

Three main meals and one to two snacks a day. Skipping a meal because you are not hungry feels efficient, but you risk too little protein and too few nutrients, and the next meal tends to be too big. The medicine turned down your hunger signal. It did not turn down your body’s need for protein, vitamins and minerals.

Eat slowly, and stop at comfortable

Fullness arrives sooner now, and your stomach empties more slowly, so the signal needs time to land. Smaller bites, fork down between them, phone away. Stop at the first sign of fullness rather than when you feel properly full - by then you have usually eaten too much.

Protein goes first

Protein is what protects your muscle while you lose weight, and it is the nutrient people on GLP-1 most often fall short on. Aim for 1.2 to 1.5 g per kg of body weight a day, with 20 to 30 g at lunch and dinner. The practical trick is to eat the protein on your plate before anything else: if you fill up halfway through, what you leave behind is the potatoes.

Make every bite count

Smaller portions leave no room for nutritional slack. The principle is not to eat less of everything, but to choose food that does more than one job - vegetables, wholegrains, legumes, dairy, fish, lean meat and eggs. Clinical guidance also recommends a daily complete multivitamin and mineral supplement on appetite-suppressing medication; ask your prescriber or a pharmacist.

Drink more than you think you need

Around 2 to 3 litres a day. You take in less water from food when you eat less, stomach side effects drain fluid quickly, and headaches, dizziness and tiredness are often the earliest signs of drinking too little. Thirst is a late signal, so drink by plan rather than by thirst.

Build fibre up slowly

Constipation is one of the most common side effects, and fibre is the best dietary defence - most adults should aim for 25 to 35 g a day. The catch is pace. Going from little fibre to a lot in a few days, especially without enough water, causes bloating and sometimes more constipation rather than less.

Lose weight slowly, on purpose

Aim for 0.5 kg a week or slightly less. Clinical guidance treats 0.5 to 1 kg a week as the maximum for weight loss that is healthy and sustainable, and the first week or two can be faster, mostly water. Losing consistently more than a kilo a week usually means you are eating too little - and the cost is muscle and nutrients. If you want the longer version, I have written about how much weight you can realistically lose in three months.

Protect your muscle

Three things protect muscle mass while you lose weight: strength training, enough protein, and losing the weight slowly. The guideline is muscle-strengthening activity at least twice a week, and it does not mean a gym and heavy weights - squats, wall push-ups, step-ups on the stairs and a resistance band all count.

Side effects, and when to call your prescriber

Nausea, constipation or diarrhoea, stomach cramps, tiredness and headaches are the common ones. They depend on the dose, they are most common in the first weeks and just after a dose increase, and for most people they ease as the body adjusts. Changing how and what you eat often makes a real difference.

See your prescriber if you have severe nausea or vomiting, stomach pain that will not settle, weight loss of more than a kilo a week, or side effects that stop you eating properly. Side effects are not a sign the medicine is wrong for you - but any change to the dose is your prescriber’s decision, never one to make on your own.

The habits are what you keep

Weight regain after stopping is common, particularly when eating habits have not changed. When you lower the dose or stop, your appetite can come back and so can the food noise. That is not failure - it is the medicine wearing off. Regular meals, protein at every meal, nutrient-dense food, enough fluid, fibre and strength training are what stay with you either way.

Where to go from here

This article is the overview. The detail is in my handbook, Eating Well on GLP-1 - how to work out your own protein target when your BMI is over 25, what to eat when nausea means nothing appeals, what actually helps for each side effect, how to build fibre without the bloating, and space to write down how each change went. It is 24 pages, and it is the support I wish everyone starting treatment had.

If you would rather make it specific to you - your food, your appetite, your week - that is what a session with a dietitian is for.

This article is general information about nutrition during treatment with appetite-suppressing medication. It is not individual medical advice, it does not replace your prescriber, doctor or dietitian, and it must not be used to start, stop or change any medication. If you have another medical condition, ask your doctor how this applies to you.