Guide

Protein on a GLP-1: the target, and how to hit it

Your appetite has gone and your protein requirement has not. This is the number, where it comes from, and what a day looks like when you can manage four bites at a time.

The short answer

1.2 to 1.6 grams of protein per kilogram of your goal body weight, which is 0.55 to 0.7 g per pound. For a 70 kg (154 lb) goal that is 84 to 112 g a day. Spread it at 0.3 to 0.4 g per kg a meal, which is 21 to 28 g a meal at that goal weight, protein first every time. Below 1.2 g per kg is where we see strength tests start to fall.

Work out your number

Why the target is set against goal weight, not current weight

Protein requirements track the amount of lean tissue you are trying to support, not the amount of fat you are carrying. Setting the number against your current weight when you have 30 kg (66 lb) to lose produces a figure nobody on a GLP-1 could eat. Setting it against goal weight gives you a target that is high enough to protect muscle and low enough to be possible on a small appetite.

So: take the weight you are heading towards, in kilograms, and multiply by 1.2 for the floor and 1.6 for the ceiling. A 65 kg (143 lb) goal gives 78 to 104 g a day. A 90 kg (198 lb) goal gives 108 to 144 g. Most people we coach sit near the middle to start and move up towards the ceiling as the weight comes off, because the same grams are protecting a smaller and smaller frame.

Two exceptions matter. If you have kidney disease, your doctor sets your protein target and this page does not apply to you. And if you are vegetarian or vegan, aim closer to the ceiling, because plant proteins are used slightly less efficiently and carry less leucine, the amino acid that signals muscle to rebuild.

Why it matters more on a GLP-1 than on any other diet

Across 20 randomised trials, an average of 35.2% of the weight lost on semaglutide (Ozempic, Wegovy) was lean mass. Losing the same weight through diet alone cost 26.2% as lean mass, which was not significantly different from the medications (p = 0.42). The muscle comes off because the weight comes off, not because of the injection. Adding resistance training brought it down to 17.5%, the most favourable result of any approach studied. Eisa N et al, Diabetes, Obesity and Metabolism 2026

Read that in order and it says something more useful than the headline usually does. The lean tissue comes off because a large amount of weight is coming off, not because of the injection, and the one thing that shifted the number in the trials was lifting something twice a week. What makes a GLP-1 different is the speed and the appetite. Losing your hunger does not remove your protein requirement, it removes the mechanism that used to make you meet it.

The practical version: before the medication you ate roughly 2,000 calories and stumbled into 80 g of protein without trying. Now you are eating 900 calories, the protein has fallen with everything else, and you are in the largest deficit of your life. That is the exact condition in which the body takes amino acids out of muscle. Our full treatment of the mechanism is in muscle loss on a GLP-1.

The per-meal number, in grams per kilogram rather than a flat 30 g

Most health sites tell everybody to eat 30 g of protein a meal. That is a reasonable average and a poor instruction, because the same 30 g is a generous serve for a 60 kg (132 lb) woman and not enough for a 100 kg (220 lb) man. Spread across meals at roughly 0.3 to 0.4 g per kg per meal, rather than taken mostly at dinner. Arslan S, Clinical Nutrition ESPEN 2026

So work it out the way you worked out your daily number, from your goal weight. A 65 kg (143 lb) goal gives 20 to 26 g a meal across four meals. A 75 kg (165 lb) goal gives 23 to 30 g. A 95 kg (209 lb) goal gives 29 to 38 g, which is why a single chicken breast does more for one person than for another. Three or four sittings at your number beats one large dinner with the same total.

Leucine, the part almost nobody tells you about

There is a reason the per-meal size matters at all, and it has a name. Each of those meals wants roughly 2.5 to 3 g of leucine, the amino acid that actually switches muscle building on. That is about 30 g of whey, 120 g of chicken breast, or four eggs. Arslan S, Clinical Nutrition ESPEN 2026

That is the mechanism behind every "eat 30 g" rule you have read: 30 g of a good-quality protein is roughly where the leucine content crosses the line that switches muscle building on. It also explains the foods that quietly fail. Porridge made with almond milk carries very little protein and almost no leucine, while four eggs carry less protein than a shake with milk and still clear the threshold. If you eat mostly plants, aim nearer the top of the daily range and make the servings larger, because plant proteins carry less leucine gram for gram. The ranked food list gives the serve size for each.

Practically, a day looks like this rather than grazing: a real protein anchor at breakfast, at lunch, in the afternoon and at dinner. If you can only manage three, make each one bigger. If you can only manage two, use a shake for the third. The guide on hitting protein on 800 calories a day works through the arithmetic when intake is at its lowest.

How to hit it when you can manage four bites

Three rules do most of the work.

Protein first, always Eat the chicken, fish, eggs or yoghurt before the rice, the bread or the vegetables. Whatever is on the plate first is what gets eaten on a small appetite.
Drink what you cannot chew A shake with milk is 33 g in ninety seconds. Soups with lentils, milk with powder stirred in, Greek yoghurt. Liquid protein goes down when solid protein will not.
Use the window Appetite is not flat across the week. On a weekly injection most people eat best on days four to seven. Put your biggest protein meals there rather than fighting for them on day one.

The protein cheat sheet lists the foods that deliver 30 g in the smallest volume, which is the metric that matters here. Anything that delivers protein in a big bowl of food is not useful to you at the moment, however good it was before.

A day at 120 g, in grams and ounces

Breakfast Three eggs with a slice of toast, about 20 g, or 200 g (7 oz) Greek yoghurt with seeds, about 25 g.
Mid-morning A 30 g scoop of whey in 250 ml (8.5 fl oz) of milk, about 33 g.
Lunch 120 g (4 oz) of chicken with salad and a roll, about 40 g.
Dinner 120 g (4 oz) of salmon or lean mince with potato and greens, about 32 g.

That is 125 g on four small plates, none of which takes long to eat. If two of those four are all you manage on a bad day, you still land near 70 g, and the weekly average is what protects you rather than any single day.

What goes wrong, in order of frequency

Counting the best day instead of the average
People quote us the Tuesday they hit 130 g. The number that predicts a falling strength test is the seven-day average, and it is usually 30 g lower than anyone expects.
Protein last on the plate
The vegetables and the carbohydrate take the room. Reverse the order and most people gain 15 g a day without changing what they buy.
Low-protein foods with a health halo
Soup, smoothies, salad, rice cakes and almond milk are all fine and none of them carry protein. On four small meals a day, every one has to earn its place.
Stopping when the weight comes off
The target follows goal weight, so it barely moves as you lose. If anything, protein matters more at the end than at the start, because there is less of you to protect.

Does the medication change the number?

Not the target. The target is set by your body and your goal weight, and it is the same on every GLP-1. What changes is how hard it is to reach, and when in the week you can reach it. On semaglutide, blood levels peak one to three days after the injection, so the first two days are usually the hardest and the last three the easiest. On tirzepatide the effect is flatter across the week, which suits a fixed daily routine better than opportunistic eating. On daily liraglutide there is no weekly rhythm at all, so consistency beats timing.

The per-medication versions of this page cover the detail: protein in your first month on Ozempic, on Wegovy, on Mounjaro, on Zepbound and on Saxenda. Whatever you are prescribed, the number is the same and the dose is your prescriber's decision, never a lever you pull to make eating easier.

What eating a lot of protein does not do

This is the part of the research we would rather you heard from us than found later. In 191 older adults, higher protein was associated with more preserved lean tissue but not with better grip strength, walking speed or chair-stand scores. Protein looks after the material. Training is what turns it into function. Eglseer D et al, Nutrition Journal 2026

So protein is not the whole answer and we will not sell it as one. Eating the target without a strength signal slows the loss of muscle; it does not keep the strength. That is the reason every page here asks for two sessions a week as well as a number in grams, and the reason we ask you to test yourself rather than trust the tissue.

The blood markers worth asking your prescriber about

Eating a third of what you used to eat cuts vitamins and minerals along with the calories, and a low-appetite diet built on toast and crackers cuts them fastest. Vitamin D, B12, iron studies, folate, zinc and thiamine are the markers this literature suggests watching. Ask your prescriber whether they are worth checking for you; we do not order or interpret bloods. Arslan S, Clinical Nutrition ESPEN 2026

Take that list to your appointment as a question rather than a request. Several of them, low iron and low vitamin D in particular, produce exactly the tiredness and hair shedding people blame on the medication, and none of them can be sorted out by guessing. Our page on fatigue and energy on a GLP-1 covers what to rule out first.

Protein alone is half the job

The other half is two 30-minute full-body sessions a week across six movements: a squat pattern, a hinge, a push, a pull, a carry and a core brace. That is the minimum that reliably holds a strength test steady while you are losing, and it is laid out in strength training on a GLP-1.

Then check it weekly. One strength test done the same way, your protein average for the seven days, and a tape measure around the upper arm. Those three numbers tell you whether you are holding onto your strength while the weight comes off, long before the mirror does.

How we work these numbers out

Three places where our advice is not a direct copy of the research, and the reasoning behind each one.

We calculate protein from goal weight, not current weight

The research states protein targets per kg of body weight. We use goal weight instead. The reason is that fat tissue has a much smaller protein requirement than muscle does, so for someone carrying a lot of weight, a target set on current body weight can produce a number nobody with a suppressed appetite will ever eat. Goal weight gives a figure that is achievable and still above the floor. If your weight is close to your goal the two numbers nearly match. If you want the literature's version, multiply your current weight in kg by 1.2.

We report ranges, not single numbers

Every pooled figure here carries a confidence interval, and the studies behind them disagree with each other more than most health articles admit. Heterogeneity in the main meta-analysis was moderate (I-squared 68%). Treat these as the shape of the problem, not as your personal forecast.

What we do not know

Nobody has shown what any of this does to the things you would actually notice: stairs, shopping bags, getting off the floor. The scans have been measured and the function has not. That is the honest state of the evidence, and it is why we ask you to test yourself every Sunday rather than trust a number from a trial that was not measuring you.

Questions people ask

How much protein should I eat on a GLP-1?

1.2 to 1.6 g per kilogram of your goal body weight, which is 0.55 to 0.7 g per pound. For a 70 kg (154 lb) goal that is 84 to 112 g a day, spread at 0.3 to 0.4 g per kg a meal. If you have kidney disease, your doctor sets your target instead.

Is that based on my current weight or my goal weight?

Goal weight. Protein tracks the lean tissue you are supporting, not the fat you are carrying, and a target set against a high starting weight would be impossible to eat on a GLP-1 appetite.

Can I get there without protein powder?

If you can eat four protein servings a day, yes. Most people at the higher doses cannot, and a shake is the easiest 30 g in the day. It is a tool for a small appetite rather than a requirement.

What happens if I do not hit the target?

In the people we coach, the strength test starts to fall within three or four weeks, usually before anything shows in the mirror. That is the early signal, and it is the point to act rather than wait.

Does protein have to be spread across the day?

It helps. Spread across meals at roughly 0.3 to 0.4 g per kg per meal, rather than taken mostly at dinner. Each of those meals wants roughly 2.5 to 3 g of leucine, the amino acid that actually switches muscle building on. That is about 30 g of whey, 120 g of chicken breast, or four eggs. Three or four servings beat one large meal with the same total.

Will hitting my protein target make me stronger?

On its own, no. In 191 older adults, higher protein was associated with more preserved lean tissue but not with better grip strength, walking speed or chair-stand scores. Protein looks after the material. Training is what turns it into function. That is why we ask for two sessions a week as well as a number in grams.

Every number on this page, and where it comes from

Five figures do the work here. The last one is the limitation, and we publish it because a protein number on its own is not the product.

Guideline-informed protein targets during this kind of weight loss start at 1.2 g per kg of body weight a day (0.55 g per lb). Arslan S, Clinical Nutrition ESPEN 2026

Up to 1.6 g per kg a day (0.73 g per lb) in adults without chronic kidney disease. Arslan S, Clinical Nutrition ESPEN 2026

Spread across meals at roughly 0.3 to 0.4 g per kg per meal, rather than taken mostly at dinner. Arslan S, Clinical Nutrition ESPEN 2026

Each of those meals wants roughly 2.5 to 3 g of leucine, the amino acid that actually switches muscle building on. That is about 30 g of whey, 120 g of chicken breast, or four eggs. Arslan S, Clinical Nutrition ESPEN 2026

In 191 older adults, higher protein was associated with more preserved lean tissue but not with better grip strength, walking speed or chair-stand scores. Protein looks after the material. Training is what turns it into function. Eglseer D et al, Nutrition Journal 2026

The papers these numbers come from

Arslan S. Medical nutrition in the glucagon-like peptide-1 (GLP-1) era: Protein strategies, micronutrient monitoring, and lean mass preservation. Clinical Nutrition ESPEN, 2026. Narrative review, guideline-informed targets. doi:10.1016/j.clnesp.2026.103305
Eglseer D, Reiter L, Schoufour JD, et al. Is higher protein intake during weight loss interventions in older adults associated with improved outcomes? A secondary data analysis of three randomised controlled trials. Nutrition Journal, 2026. 191 adults, mean age 65.1 years. doi:10.1186/s12937-025-01279-2
Eisa N, Barood O. Lean Mass Changes With Incretin Therapy Versus Lifestyle Intervention: A Systematic Review and Meta-Analysis of Randomised Controlled Trials. Diabetes, Obesity and Metabolism, 2026. 20 randomised controlled trials, 15,782 participants. doi:10.1111/dom.70666

Last reviewed 18 September 2026. We update these figures when a larger or better study replaces them, and we say what changed. How we handle evidence.

The free tools that go with this

The protein calculator Your daily target in grams from your goal weight, with a sample day at that number.
The protein cheat sheet One page, forty foods, grams of protein per serve in metric and imperial.
The muscle or fat quiz Six questions that tell you whether what you are losing is the tissue you wanted to lose.
The Personal 7-Day Plan Your week of meals built to your target and your appetite, A$19 / US$12 / £9.

The Keep Muscle Kit

Meal plans at 100, 120 and 140 g of protein

The workbook, Sunday numbers tracker, 2-day strength plan, injection-day card, and meal plans at 100, 120 and 140 g protein. Instant download.

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