What not to eat on GLP-1 medication, and what to eat instead

There is no banned-food list for GLP-1 medications, but a few kinds of food cause most of the trouble: fried and greasy food, rich creamy dishes, very sugary food and drinks, alcohol, fizzy drinks, big portions, and, for some people, very spicy food and big hits of fibre or sugar alcohols. They tend to bring on nausea, reflux, bloating or diarrhoea, and they fill a small appetite without much protein.

Below: why each one is a problem, which side effect it tends to worsen, a swap that keeps the meal you like, how much is usually fine, and how to order when you eat out.

Why some foods are harder on GLP-1 medication

Two things change when you take semaglutide (Ozempic, Wegovy) or tirzepatide (Mounjaro, Zepbound).

• Food leaves your stomach more slowly. The prescribing information for each medication says it delays gastric emptying. Food that is already slow to digest, like fat, sits even longer. That fullness can turn into nausea, burping or heartburn.
• You eat much less. Appetite drops, so every bite takes up more of the day's small space. Foods with little protein or nutrition push out the ones that protect your muscle while the weight comes off.

Stomach side effects are common. In the Wegovy trials, 44% of people on the drug reported nausea, 30% diarrhoea, 24% vomiting and 24% constipation, according to its label; for Zepbound, the label lists nausea in 25–29% depending on dose. They are most common in the first weeks and after each dose increase. What you eat won't remove them, but it can make them better or worse.

The foods to limit, at a glance

1. Fried and greasy food

Fries, fried chicken, onion rings, doughnuts, fatty burgers, pizza with a lot of cheese, bacon in quantity. This is the group most people on these medications learn to fear: a few bites can sit for hours, and many people say it is what brings on their worst nausea or "sulfur burps."

Instead: the same food baked, grilled or air-fried. Grilled chicken instead of fried; a lean beef or turkey burger on a bun with salad instead of a double with fries; oven potato wedges with a little oil; thin-crust pizza with chicken and vegetables, one or two slices with a salad.

2. Rich, creamy dishes

Alfredo and cream sauces, mac and cheese, creamy soups, gravy, cheesecake, big cheese boards. They pack a lot of fat into a small bowl, so you feel full quickly but have eaten little protein.

Instead: tomato or broth-based sauces; a "cream" sauce made with blended cottage cheese or Greek yogurt (more protein, much less fat); broth soups with chicken, beans or lentils; a small piece of cheese next to fruit instead of a board.

3. Sugary drinks, sweets and desserts

Soda, sweet coffee drinks, juice, milkshakes, candy, pastries, ice cream. They take up appetite you need for protein, and big amounts of sugar on an empty stomach can upset it. The 2025 joint nutrition advisory for people on GLP-1 treatment from four US obesity and nutrition societies advises limiting sugar-sweetened drinks, sweets and highly processed foods.

Instead: water, sparkling water if fizz doesn't bother you, tea, milk or ultra-filtered milk; Greek yogurt with berries and a little honey; a protein pudding or a frozen yogurt bark; a square or two of dark chocolate after a meal. If you have diabetes and take insulin or a sulfonylurea, keep a fast sugar on hand for lows; that's a medical need, not a treat.

4. Refined starches on their own

White bread, crackers, chips, pretzels, plain pasta, sugary cereal. They aren't harmful in a meal, but eaten alone they are the classic "I ate all day and got 30 g of protein" food. They are also low in fibre, which matters when constipation is a common side effect.

Instead: keep the starch, shrink it, and pair it: crackers with cottage cheese or tuna; whole-grain toast with eggs; pasta with chicken or lentils and vegetables, the pasta a quarter of the plate. Whole-grain and higher-fibre versions add fibre slowly.

5. Alcohol

Alcohol irritates the stomach and adds to fluid loss, so it can make nausea, vomiting and dehydration worse. Many people also find their tolerance feels lower on these medications. The labels warn that GLP-1 medications used with insulin or a sulfonylurea raise the risk of low blood sugar, and alcohol can lower blood sugar further. The labels also list pancreatitis as a possible risk, and heavy drinking is a known cause of pancreatitis.

Instead: if you drink, keep it to one, with food, slowly, and with water alongside. Alcohol-free beer or wine, sparkling water with lime, or a kombucha (if fizz is fine for you). Ask your prescriber what's safe for you if you have diabetes or a history of pancreatitis.

6. Fizzy drinks

Carbonation puts gas into a stomach that's already slow to empty. Some people are fine; others get bloating, burping and reflux.

Instead: still water with fruit, iced tea, or let sparkling water go flat. Diet soda counts as fizzy too.

7. Very spicy or acidic food

Hot sauce, chilli, very peppery curries, and for some people tomato sauce, citrus and coffee. These don't bother everyone; they are a problem mainly if you get reflux or heartburn, which a full, slow stomach makes more likely.

Instead: milder versions, herbs and garlic for flavour, and smaller portions eaten earlier in the evening. If coffee bothers you, try it after food rather than on an empty stomach.

8. Big hits of fibre, and sugar alcohols

Fibre helps with constipation, and most adults need 22–34 g a day (Dietary Guidelines for Americans). The problem is a lot at once: a big bean chilli, a large raw salad, a high-fibre bar, a fibre supplement added on day one. In a slow gut, that can mean gas and cramps.

Sugar alcohols (sorbitol, maltitol, erythritol, xylitol) are in many protein bars, "keto" sweets and sugar-free gum. In larger amounts they often cause gas and diarrhoea, in anyone. Our guide to protein bars on GLP-1 shows which label lines to read.

Instead: add fibre 3–5 g at a time over a couple of weeks, drink more as you do, and prefer cooked vegetables to big raw salads early on. Our guide on protein and fiber goals on GLP-1 has a slow build-up.

9. Big portions of anything

This one surprises people: a large plate of perfectly healthy food can make you as sick as a fried meal. Your stomach holds food longer, so eating "until full" often means eating past it. Fullness can catch up 15–20 minutes later.

Instead: a 9-inch plate or a bowl; protein first; put the fork down between bites; stop at "comfortable," and keep the rest for two hours later. Four or five small meals a day work better than three big ones. See what to eat in a day on GLP-1 for full days built this way.

Swaps that keep the meal you like

Grams are rounded from USDA FoodData Central values and typical portions; your brands will differ.

Do you have to cut these foods out completely?

No. The dietitians and the 2025 advisory talk about limiting, not banning. What tends to work:

• Test, don't guess. Some people handle pizza fine and get sick on a creamy soup. Notice what your own triggers are over two or three weeks.
• Small amounts, after protein. A few fries after a grilled chicken salad is a different meal than a basket of fries.
• Not on hard days. In the first weeks, after a dose increase, and in the day or two after your shot if that's when you feel worst, keep to plain food.
• Mind the timing. Rich or large meals late in the evening are the most likely to cause reflux at night. Finish 2–3 hours before lying down.

Eating out and takeaway

• Order grilled, baked, roasted or steamed. Ask for sauce on the side.
• Start with the protein: a lean main, a starter of shrimp, chicken skewers or a broth soup.
• Order a starter as your main, or plan to box half before you start.
• Choose sides like salad, vegetables, rice or a baked potato over fries.
• Have one drink at most, or none. Ask for water as soon as you sit down.

What to eat more of

Avoiding foods is only half the job. On these medications, the bigger risk is not eating enough of the right ones. Build each meal on 20–30 g of lean protein (chicken, fish, eggs, Greek yogurt, cottage cheese, tofu, beans and lentils), add vegetables or fruit, and a small whole-grain starch. Our guide to the best protein sources on GLP-1 lists 25 foods with grams, and the GLP-1 meal plan for beginners puts them into a week.

Not sure whether you're getting enough? The free 2-minute protein check gives your daily number in grams.

When to call your prescriber

• You can't keep food or fluids down for more than a day, or you have signs of dehydration (dizziness, very dark urine, little urine).
• Severe stomach pain that doesn't go away, with or without vomiting, especially if it spreads to your back. The labels list pancreatitis and gallbladder problems as possible risks.
• Pain in the upper right belly, fever, or yellow skin or eyes.
• Symptoms of low blood sugar (shaking, sweating, confusion) if you take insulin or a sulfonylurea.

Questions people ask

What foods make Ozempic side effects worse?

Fried and greasy food, rich creamy dishes, very sugary food and drinks, alcohol, and large portions are the most common triggers. Fizzy drinks and spicy food bother some people.

Can I eat pizza on a GLP-1?

Yes, in a small portion. Thin crust, lean toppings like chicken and vegetables, one or two slices with a salad, and not on your hardest days.

Can I drink coffee on GLP-1 medication?

Most people can. If it upsets your stomach or reflux, have it after food, make it smaller, or switch to a latte made with milk, which also adds protein.

Is it OK to drink alcohol on a GLP-1?

The labels don't ban it, but it can worsen nausea and dehydration, and with insulin or a sulfonylurea it adds to the risk of low blood sugar. If you drink, keep it to one with food, and ask your prescriber what's safe for you.

Should I avoid carbs on a GLP-1?

No. You don't need a low-carb diet. Keep starches small, choose whole-grain ones, and eat them with protein rather than on their own.

Why do I get sulfur burps on Mounjaro or Ozempic?

Food sits in the stomach longer, and many people notice it most after fatty, large or high-protein meals eaten fast. Smaller meals, eating slowly, and avoiding greasy food and fizzy drinks often help. If it comes with pain or vomiting, call your prescriber.

To find your own protein target and the meals that leave you short, take the free 2-minute protein check. More on eating and training on weight-loss medication: all our muscle plan guides.

Sources: US prescribing information for Wegovy, Ozempic, Zepbound and Mounjaro (delayed gastric emptying; gastrointestinal adverse reactions and their rates; low blood sugar with insulin or sulfonylureas; pancreatitis; gallbladder disease; dehydration and kidney injury). Mozaffarian D. et al., "Nutritional priorities to support GLP-1 therapy for obesity", joint advisory of ACLM, ASN, OMA and TOS, Am J Clin Nutr, 2025. Dietary Guidelines for Americans (fibre). NIDDK, "Pancreatitis" (alcohol as a cause). USDA FoodData Central (protein values). This guide is about food and habits and is not medical advice; keep to your prescriber's advice.