On a GLP-1 you will eat something like a third less than you used to, without deciding to. Protein is the first thing to disappear from a smaller plate, and it is the thing you can least afford to lose.
The reason is not aesthetic. When weight comes off fast without enough protein and without loading your muscles, a much larger share of what you lose is lean tissue rather than fat. The scale looks identical either way. The body composition does not.
How much protein
The range that comes out of the weight-loss nutrition evidence is 1.2–1.6 g of protein for every kg you weigh, each day, and it is anchored to lean mass — so if your BMI is over 30, work from your ideal body weight rather than what the scale says today.
| Body weight | Grams per day | What that looks like |
|---|---|---|
| Under 150 lb | 65 to 80 g | Three eggs plus a cup of Greek yogurt plus 4 oz chicken gets you to about 66 g |
| 150 to 200 lb | 80 to 110 g | A shake, a cup of cottage cheese, 5 oz of fish, two eggs ≈ 96 g |
| Over 200 lb | 100–130 g | Two shakes, 6 oz of chicken, a cup of Greek yogurt, two eggs ≈ 124 g |
| Lifting regularly | Add about a fifth | An extra serving of fish or poultry on training days |
These are daily totals, not per meal. Spreading them across the day is easier on a stomach that is emptying slowly anyway.
Where to get it
- Chicken breast — about 25 g per cooked 3 oz. The most protein per calorie of any whole food here.
- Plain Greek yogurt — 15 to 20 g a cup, and considerably kinder than meat in the early weeks.
- Eggs — 6 g each. Two at breakfast is 12 g before anything else happens.
- Cottage cheese — 12 to 14 g per half cup, and slow-digesting, which suits the evening.
- Fish — 20 to 25 g per 3 oz, across salmon, cod, tuna or tilapia.
- A protein shake — 20 to 30 g a scoop, and the single easiest way to close a gap on a day when food is unappealing.
- Lentils, beans, chickpeas — 8 to 15 g a cup. Bring the fiber up gradually rather than all at once.
What a slowed stomach actually tolerates
- Room temperature beats extremes. Very cold or very hot food provokes nausea when things are moving slowly.
- Keep it plain on dose weeks. Injection day and the two or three days after are the worst of it.
- Add fiber gradually — about 5 g a day at a time. A sudden pile of it on a slowed stomach means cramping and bloating.
- Two liters of water a day, minimum. The labels warn about kidney injury when someone gets dry, and this is the cheapest possible insurance.
- Smaller and more often. A distended stomach is the commonest nausea trigger there is.
- Eat slowly and chew properly. Fullness now arrives late, so stopping at comfortably full means stopping earlier than feels natural.
What to pull back on
- Alcohol. Pancreatitis is on these labels as a warning, and drinking is the commonest everyday contributor to it. Our page on drinking covers what the label does and does not say.
- Fatty meals while titrating. Fried things, creamy sauces and big fatty cuts are the dependable triggers for reflux and nausea in the first month or so.
- Gas-producing food early on — raw cruciferous vegetables, raw onion, fizzy drinks.
- Big portions. Forcing a slowed stomach to stretch is the most dependable way to be sick.
- Calories you drink. Smoothies, juice and sweetened coffee deliver energy without triggering the fullness that solid protein does — the one category that gets past the drug's main mechanism.
The trap
⛔ Not being hungry is not the same as not needing to eat. The pattern shows up at three to six months: tired out of proportion to the weight lost, hair shedding, progress slowing after the initial drop, and a body-composition scan showing far more lean mass gone than there should be.
If food will not get you to the target on a given day, a 25 to 30 g shake is the lowest-effort fix available and it is a perfectly legitimate meal.
The other half of the answer
Protein alone does not do it. In a one-year randomized trial of 195 adults that the New England Journal of Medicine carried in 2021, participants were assigned to liraglutide, to supervised exercise, to both, or to neither after an initial low-calorie diet. Exercise on its own protected lean mass; combining it with the drug produced the best body composition of any group.
So the evidence-backed combination is the protein target above plus two or three resistance sessions a week. Our training card covers what those sessions should contain.
What this does not cover
General adult nutrition only. Carb counting for diabetes, protein restriction in kidney disease (where the target may run far lower, in the opposite direction to everything above), pre-surgical diets, pregnancy and children all need a dietitian and your prescriber rather than a reference card.
Where to go next
- Hair loss and muscle loss — what actually drives both, and what prevents them.
- Exercise and strength training — the companion to this page.
- Protein calculator — the table above with ideal body weight built in.
- All cheat sheets — the full reference library.