On a GLP-1 medication such as Ozempic, Wegovy, Mounjaro or Zepbound, the main nutrition goal is to get enough protein while you eat less. A 2025 joint advisory from four US obesity and nutrition societies notes that 1.2 to 1.6 g of protein per kg of body weight a day has been proposed during active weight loss, or a simpler 80 to 120 g a day.
Around that protein, the advice is plain: small regular meals, plenty of vegetables, fruit, whole grains, beans and dairy, enough fluids, little alcohol, and strength training. The answers below go through the questions people ask most, with the source for each.
Key takeaways
- Protein: 1.2-1.6 g/kg a day has been proposed during weight loss; for a 180 lb (82 kg) adult that's about 98-131 g.
- Calories drop 16-39% on these medications, which raises the risk of vitamin and mineral shortfalls.
- Muscle: in the STEP 1 trial, 38% of weight lost was lean mass; protein plus strength training helps protect it.
- Side effects: nausea affects 25-44% of people in trials; small, frequent, low-fat meals help.
- Stopping: people regained about two-thirds of lost weight within a year after stopping semaglutide.
GLP-1 nutrition targets at a glance
| Target | Amount | Source |
|---|---|---|
| Protein, general adult RDA | 0.8 g/kg (0.36 g/lb) a day | 2025 joint advisory |
| Protein during active weight loss | 1.2-1.6 g/kg (0.55-0.73 g/lb) a day, or 80-120 g a day | 2025 joint advisory |
| Protein floor and ceiling | Not below 0.4-0.5 g/kg; avoid long-term intake at 2 g/kg or more | 2025 joint advisory |
| Calories, nutrient-risk zone | Below about 1,200 a day (women) or 1,800 (men) | 2025 joint advisory |
| Fiber | 22-34 g a day for adults, raised gradually | Dietary Guidelines for Americans |
| Activity | At least 150 min of moderate cardio a week, plus strength training at least 3 times a week | 2025 joint advisory |
Work out your own number with the protein calculator. Our protein requirements on Ozempic guide walks through the math by body weight.
What to eat on a GLP-1
What should I eat on Ozempic or Zepbound?
The joint advisory lists foods to encourage: fruits, vegetables, whole grains such as oats, quinoa and brown rice, dairy like yogurt and cheese, lean poultry, fish and eggs, nuts and seeds, beans and lentils, and plant oils such as olive or canola. Eat the protein part of the meal first, so it doesn't get left behind when you fill up.
What foods should I avoid on Ozempic?
No food is banned, but the advisory suggests minimizing:
- Refined carbs: white flour, pastries, added sugar
- Sugar-sweetened drinks
- Red and processed meats
- Most fast food, sweets and salty snacks
Greasy, fried and very large meals are also the ones most likely to set off nausea, because these drugs slow how fast your stomach empties.
How many calories should I eat?
There's no single target. In studies, people taking GLP-1 medications ate 16-39% fewer calories. The advisory warns that shortfalls in vitamins and minerals become more likely below about 1,200 calories a day for women and 1,800 for men. If you're regularly below that, tell your care team. A TDEE calculator gives you a starting point for your maintenance needs.
Can I eat carbs on a GLP-1?
Yes. Whole grains, fruit, beans and starchy vegetables are on the advisory's "encourage" list. The carbs to cut back are refined ones and sugary drinks, which bring calories without much protein, fiber or fullness.
Is intermittent fasting OK on a GLP-1?
The advisory points out that many people on these drugs end up fasting without meaning to, simply because they aren't hungry. It recommends eating at regular times of day, because long gaps without enough protein can lead to nutrient gaps and loss of lean mass. If you take insulin or a sulfonylurea for diabetes, fasting can also raise the risk of low blood sugar, so check with your prescriber first.
Protein and muscle
Will I lose muscle on a GLP-1?
Some, yes. In the STEP 1 semaglutide trial, people lost an average of 13.6 kg (30 lb): 8.3 kg (62%) was fat and 5.3 kg (38%) was lean mass. Because muscle is about half of lean mass, roughly 20% of the weight lost was muscle. The advisory says structured strength training, or strength plus cardio, protects lean mass better than cardio alone. More on this in our Ozempic muscle loss guide.
What are the best protein foods when your appetite is low?
Pick foods that pack a lot of protein into a small volume. All values from USDA FoodData Central.
| Food | Portion | Calories | Protein (g) |
|---|---|---|---|
| Chicken breast, roasted | 3 oz (85 g) | 140 | 26.4 |
| Greek yogurt, nonfat, plain | 6 oz (170 g) | 100 | 17.3 |
| Tofu, firm | 3 oz (85 g) | 122 | 14.7 |
| Cottage cheese, 1% | 1/2 cup (113 g) | 81 | 14.0 |
| Lentils, cooked | 1/2 cup (99 g) | 115 | 8.9 |
| Egg, large | 1 egg (50 g) | 72 | 6.3 |
Protein shakes help on days solid food is hard. Check the label for the protein per serving and keep added sugar low.
Vitamins and supplements
Do GLP-1 medications cause vitamin deficiencies?
They can make them more likely, because you eat less. The advisory names iron, calcium, magnesium, zinc and vitamins A, D, E, K, B1, B12 and C as nutrients of concern. Warning signs include unusual tiredness, heavy hair shedding, flaky or itchy skin, muscle weakness, slow wound healing and easy bruising.
What supplements should I take?
The advisory says supplements "can be proactively considered" for at-risk nutrients such as vitamin D, calcium, B12 or a multivitamin-mineral, at doses tailored to you. That's a conversation for your clinician, ideally with blood work. Our supplements on Ozempic guide covers the options.
Side effects and food
How do I manage nausea?
Nausea is the most common side effect: 25-44% of trial participants, most often when starting or after a dose increase. The advisory's food tips:
- Eat a small breakfast, then small meals every 3-4 hours.
- Sip fluids through the day.
- In the first days of a new dose, go easy on fatty and high-fiber foods.
- Try ginger or peppermint tea.
See Ozempic nausea foods for gentle meal ideas.
What helps with constipation?
Constipation affects 17-24% of people in trials. Drink enough fluids and add fiber from food slowly; prunes and other dried fruit are a common first step. Protein-heavy and fatty meals slow digestion further, so balance them with fruit and vegetables. Our Ozempic constipation guide has a full fiber plan.
Why do some foods suddenly taste wrong?
Many people notice their food preferences shift on a GLP-1. The advisory's writing group reports that cravings for high-fat foods, sweets and alcohol often fade, while nausea can push some people toward refined comfort foods. If meat turns you off, lean on eggs, dairy, fish, tofu and beans instead.
Does Ozempic cause hair loss?
Hair loss is listed among the less common side effects, and heavy hair shedding is also a sign of low nutrient intake. Getting enough protein and calories, and checking iron, zinc and other levels with your clinician, are the sensible first steps.
Alcohol, exercise and plateaus
Can I drink alcohol?
The advisory recommends minimal alcohol. Drinks add calories without protein, and alcohol can make nausea and reflux worse.
Should I exercise on a GLP-1?
Yes. The advisory says GLP-1s should be prescribed together with a structured exercise program: strength training at least 3 times a week plus at least 150 minutes of moderate cardio, such as brisk walking. That's one more strength day than the general US activity guidelines, which call for muscle-strengthening work on 2 or more days.
What if my weight loss stalls?
Check the basics first: portions creep up as appetite returns, and protein often slips. Log a few typical days, recheck your protein against your current weight, and keep up strength training. If the stall lasts several weeks, talk to your prescriber about your dose and plan.
Stopping a GLP-1
What happens when you stop?
In the STEP 1 extension, people had lost 17.3% of their body weight after 68 weeks on semaglutide. One year after stopping, they had regained 11.6 percentage points, about two-thirds of the loss, and most cardiometabolic gains faded too. The researchers concluded that ongoing treatment is likely needed to keep the results.
In everyday practice many people stop sooner than in trials: the advisory cites about 33-50% still taking the drug at 1 year and 15% at 2 years. Habits built while on the drug, especially protein intake and strength training, matter most for what happens after. Our guide to maintaining weight after Ozempic covers the transition.
This page is general information, not medical advice. Talk to your doctor or a registered dietitian before changing your diet, supplements or medication.
Tracking protein on a GLP-1
When you're eating less, it's easy to fall short on protein without noticing. Nutrify lets you log a meal from a photo and shows protein against your daily target, so a low day is obvious by lunch. Nutrify has a 7-day free trial, then a paid subscription.
Sources
- Mozaffarian D, et al. Nutritional priorities to support GLP-1 therapy for obesity: a joint Advisory from the American College of Lifestyle Medicine, the American Society for Nutrition, the Obesity Medicine Association, and The Obesity Society. Am J Clin Nutr. 2025. Full text: PMC12612741.
- Wilding JPH, et al. Weight regain and cardiometabolic effects after withdrawal of semaglutide: the STEP 1 trial extension. Diabetes Obes Metab. 2022.
- U.S. Department of Health and Human Services, Physical Activity Guidelines for Americans, 2nd edition.
- U.S. Department of Agriculture and HHS, Dietary Guidelines for Americans, 2020-2025 (fiber targets by age and sex).
- USDA FoodData Central: chicken breast, roasted, FDC 171477; Greek yogurt, nonfat, FDC 170894; tofu, firm, FDC 172475; cottage cheese, 1%, FDC 173417; lentils, cooked, FDC 172421; egg, whole, FDC 171287.
