The GLP-1 nutrition guide: what to eat, drink and watch

Short answer: on a GLP-1 medication people eat 16% to 39% less, so each small meal has to carry more.^[1] Put protein first, add fiber from food slowly, drink on a schedule rather than on thirst, and watch the nutrients a 2025 joint advisory flags as at risk, such as vitamin D, calcium and B12.^[1]

This page is a map. Each section below answers one question in a few lines and points to the article that covers it in full, with its own sources. If you would rather read one long piece from start to finish, start with our guide to what to eat when you're eating less; this page sorts the same ground by question.

What are the key numbers on a GLP-1?

None of these numbers is specific to GLP-1 medications. They are the general reference intakes for healthy adults, and the starting point the detailed articles work from. Your clinician's figure replaces any of them if you have one.

What	Reference for adults	The full article
Protein	0.8 g per kg of body weight a day (RDA); 1.2 to 1.6 g/kg proposed while weight is coming down[1][2]	How much protein on a GLP-1
Fiber	14 g per 1,000 calories eaten; the label Daily Value is 28 g[3][4]	How much fiber a day on a GLP-1
Fluid from drinks	about 2.2 L (9 cups) a day for women, 3 L (13 cups) for men[5]	How much water to drink on a GLP-1
Sodium, potassium, magnesium	Daily Values of 2,300 mg, 4,700 mg and 420 mg[4]	How to choose an electrolyte drink
Vitamins and minerals	vitamin D, calcium and B12 are the ones the advisory names as worth considering[1]	Which vitamins matter on a GLP-1

What should you eat on a GLP-1?

There is no official GLP-1 diet. The pattern the 2025 advisory describes is ordinary healthy eating in smaller amounts, built around protein, with fruit or vegetables and whole grains, and for unsettled days it suggests a small breakfast, then small meals every three to four hours with enough fluid.^[1]

• The plate, in order, with a sample day: what to eat on a GLP-1.
• Where the phrase comes from and what it is not: what is the GLP-1 diet?
• Days when nothing appeals: what to eat when you're not hungry.
• When the day has shrunk to a single sitting: eating once a day on a GLP-1.
• What tends to sit badly, and what to choose instead: foods to avoid on a GLP-1.
• Eating enough when appetite is small, and the calorie ranges behind it: how many calories to eat on a GLP-1.
• Small, protein-first dishes that take five minutes: GLP-1 recipes.
• Eighteen small snacks with the protein and water in each: GLP-1 snacks.

How much protein do you need on a GLP-1?

At least the RDA of 0.8 g per kilogram of body weight a day, and the advisory notes that 1.2 to 1.6 g/kg has been proposed while body weight is coming down.^[1][2] For a 75 kg (165 lb) adult that is 60 g at minimum and 90 to 120 g at the higher range. Protein comes first on the plate because low protein intake on a reduced appetite can add to muscle loss, and the advisory pairs it with resistance or strength training as the two measures for keeping muscle.^[1]

• The numbers by body weight, and how to reach them with a small appetite: how much protein on a GLP-1.
• Strength training, lean mass and who is most at risk: keeping muscle on a GLP-1.
• Reading a protein powder label, whey versus plant, and what a lead test found: the best protein powder for a GLP-1.
• Your own target in grams: our protein calculator.

How much fiber do you need on a GLP-1?

The Dietary Guidelines set 14 g for every 1,000 calories, about 20 g a day at 1,400 calories.^[3] The difficulty is fitting it into much less food, and the advisory notes that fatty and high-fiber foods can be harder to tolerate in the first days of a new dose.^[1] Build up slowly, from food first, with fluid alongside.

• The number by calories eaten, and the foods with the most fiber per bite: how much fiber a day on a GLP-1.
• Fiber, fluid, movement and meal timing together: fiber and staying regular on a GLP-1.
• Psyllium, PHGG, inulin and methylcellulose side by side: fiber supplements compared.

How much water should you drink, and do you need electrolytes?

The National Academies' reference is about 2.2 liters of drinks a day for women and 3 liters for men, more with activity or heat.^[5] About 20% of water normally comes from food, so eating less removes some of it, and the prescribing labels warn that fluid lost through vomiting or diarrhea can lead to acute kidney injury.^[5][6][7] Eating less also means less of the minerals that arrive with food, which is why sodium, potassium and magnesium come up on low-appetite days.

• The daily number and a simple drinking schedule: how much water to drink on a GLP-1.
• Why you may not feel thirsty, and when a dry day needs a call: GLP-1s, thirst and dehydration.
• Milk, broth, tea, coffee and the drinks to limit: what to drink besides water.
• Coffee, the 30-minute rule for semaglutide tablets and caffeine per cup: coffee on a GLP-1.
• Drinking alcohol on these medications: can you drink alcohol on a GLP-1?
• When extra electrolytes make sense, and who should ask first: do you need electrolytes on a GLP-1?
• Reading an electrolyte label in milligrams: how to choose an electrolyte drink.
• A rough figure for your own day: our hydration calculator.

Which vitamins and minerals run low?

The advisory lists vitamins A, D, E, K, B1, B12 and C, plus iron, calcium, magnesium and zinc, as the nutrients most likely to fall short, and says supplements "can be proactively considered for at-risk nutrients, such as vitamin D, calcium, B12, or a multivitamin-mineral tablet, at appropriate doses and tailored to each person's needs".^[1] A blood test tells you which apply to you.

• Nutrient by nutrient, with the signs worth acting on: which vitamins matter on a GLP-1.
• The shortlist, what to look for on a label and what to avoid: what supplements to take with a GLP-1.
• Products marketed to people on these medications: what they are, and what no supplement can do.

For transparency about our own product: Zornava Replenish is a lemon-lime drink mix with sodium, potassium, magnesium and calcium, a prebiotic fiber (partially hydrolyzed guar gum) and vitamins C, D3, B1, B6, folate and B12 with zinc. It has no protein, no iron and no vitamins A, E or K, so it is not a meal or a multivitamin, and it sits beside the food in every section above rather than in place of it.

What about tiredness, hair shedding and queasy days?

Each of these is listed in at least one prescribing label, and each has a food-and-fluid side worth checking. In the Wegovy trials, 11% of adults reported fatigue or weakness against 5% on placebo.^[6] In the Zepbound trials, fatigue was reported by 5% to 7% depending on dose against 3% on placebo, and hair loss by 4% to 5% against 1%.^[7] The shedding usually described is telogen effluvium. A 2020 review notes that it can follow calorie restriction, generally starts two to three months after the trigger, and in its acute form lasts under six months and resolves in around 95% of cases.^[8]

• The ordinary causes, most common first: why GLP-1s can leave you tired.
• Shedding versus balding, and what to test: GLP-1 medications and hair shedding.
• Small amounts, often, and fluids through the day: what to eat on queasy days.

Is there a page for your medication?

Semaglutide is sold as Wegovy and Ozempic; tirzepatide as Zepbound and Mounjaro. The food advice is the same across them, but each label records different trial figures, so these pages quote the label for that drug.

Question	Wegovy or Ozempic (semaglutide)	Zepbound or Mounjaro (tirzepatide)
What to eat	What to eat on Wegovy or Ozempic	What to eat on Zepbound
Tiredness	Does Wegovy or Ozempic make you tired?	Does Zepbound make you tired?
Hair shedding	GLP-1 medications and hair shedding	Zepbound, Mounjaro and hair shedding
Staying regular	Fiber and staying regular on a GLP-1	Zepbound: fiber, fluid and when to call

Retatrutide, nicknamed "GLP-3", is not approved yet. What its trials found and where approval stands are in GLP-3 (retatrutide) explained.

Which tools put numbers on your own day?

• Nutrition gap calculator: tap what you ate and drank today to see roughly how far it falls from the reference intakes.
• Protein calculator: your daily protein range in grams from your body weight.
• Hydration calculator: a rough daily fluid figure adjusted for activity and weather.
• The Eating-Less Nutrition Gap: our report on where a small-appetite day usually falls short, with its sources.

When should you talk to your prescriber?

When you cannot keep fluids down, are passing very little urine, feel faint on standing or confused, when tiredness is severe or does not ease, or when you are eating so little that a whole day goes by with almost nothing. Each detailed article ends with the signs specific to its topic. The advisory also points to a registered dietitian as one of the main supports for people on these medications.^[1]

Not sure which part of your intake is slipping on lighter days? Our two-minute quiz sorts it into water, protein, fiber and vitamins.