Protein · Daily target
How much protein do you actually need?
Protein is the single biggest lever for keeping muscle while you lose fat — especially on a GLP-1, where appetite drops fast and lean mass can drop with it. Get your daily target below.
lbs
In a caloric deficit. Higher protein protects lean mass while body fat drops.
Daily protein target
130g / day
Evidence-based range: 114–180 g · 1.6 g/kg · 0.73 g/lb
Per meal · 4 meals / day
≈ 35g per meal
Muscle protein synthesis peaks at roughly 30–40 g per meal in most adults — spreading intake across the day works better than loading it all at dinner.
What ~30 g of protein looks like
- Chicken breast4 oz cooked31g
- Greek yogurt (non-fat)1.5 cups30g
- Salmon4 oz cooked29g
- Ground beef (90/10)4 oz cooked30g
- Whey protein1 scoop25g
- Cottage cheese (low-fat)1.25 cups30g
- Eggs5 large30g
- Tofu (firm)8 oz22g
- Lentils (cooked)1.5 cups27g
- Tuna (canned, water)5 oz can30g
Ranges synthesize ISSN protein position statements and body-composition analyses from STEP 1 (Wegovy® semaglutide) and SURMOUNT-1 (Zepbound® tirzepatide). Targets are class-level guidance for muscle-mass preservation and are not outcome predictions for any compounded preparation. If you have kidney disease, talk to your provider before increasing protein.
Background
Why protein is the lever
Body weight is two pools — fat mass and lean mass — and when you lose weight, both move. The goal of any sensible weight-loss plan is to shift that ratio: lose as much fat as possible while holding onto as much muscle as possible. Protein is the most evidence-supported nutritional lever for doing that. Calories decide whether you lose weight at all; protein decides what kind of weight you lose.
What the GLP-1 trials showed
Body-composition substudies of STEP 1 (Wegovy® semaglutide 2.4 mg) and SURMOUNT-1 (Zepbound® tirzepatide 15 mg) measured lean mass alongside total weight loss. In both trials, lean mass made up a meaningful fraction of the total loss when no protein or resistance-training intervention was specified. That's an unsurprising result of any large caloric deficit — but it's avoidable. Trials that combined GLP-1 therapy with deliberately high protein intake and resistance training consistently preserve more lean mass. These findings come from trials of FDA-approved products and are not outcome predictions for compounded preparations.
The simple playbook
- Hit the daily target above — split across 3–4 meals of 30–40 g each.
- Front-load protein at breakfast and lunch when appetite is more reliable; dinner can be lighter.
- Default to lean animal protein, dairy, or soy — they have the highest leucine content per gram, which drives muscle protein synthesis hardest.
- Resistance train 2–3 times per week. Protein without lifting is half the equation.
- If you can't eat enough whole-food protein, a whey or plant-based protein shake is a clean tool. Most people on a GLP-1 use at least one shake per day in months 3–6.
See it next to your calorie target
Protein doesn't live in a vacuum — it's part of your total calorie budget. Run the TDEE calculator to see your daily calorie target alongside the protein number, then check the projection calculator to see what 12 months on an FDA-approved GLP-1 looks like in published trials.
FAQ
Common protein questions
How much protein should I eat per day?+
For weight-stable adults, 1.0–1.4 g per kg of body weight covers general health and active living. In a caloric deficit, 1.4–2.2 g/kg better protects lean mass. On a GLP-1 in active weight loss, aim for the top of the range — 1.6–2.4 g/kg — because appetite suppression makes it easier to lose muscle alongside fat if protein intake drifts low.
Why does protein matter more on a GLP-1?+
Body-composition data from STEP 1 (Wegovy® semaglutide) and SURMOUNT-1 (Zepbound® tirzepatide) showed that lean mass made up a meaningful fraction of total weight lost when protein and resistance training weren't prescribed. Higher daily protein intake — paired with strength training — is the most evidence-supported way to shift that ratio toward fat loss and away from muscle loss. These body-composition findings come from trials of FDA-approved products and have not been independently established for compounded preparations.
Should I calculate protein based on current or goal weight?+
For most adults, calculating off current body weight works well. If you're carrying significant excess fat (BMI well over 30), some clinicians prefer lean body mass or a goal weight to avoid overshooting — 2.4 g/kg of a 300 lb body weight (≈330 g) is hard to actually eat. As a practical ceiling, most adults plateau in benefit around 2.0–2.2 g/kg of current weight or about 1 g per pound of goal weight, whichever is lower.
What if I can't eat that much protein on a GLP-1?+
Appetite suppression is real and is often the hardest part of staying compliant. Start with high-protein, low-volume foods at the front of each meal — Greek yogurt, eggs, whey shakes, chicken, fish, cottage cheese, tofu. Front-loading protein at breakfast and lunch tends to work better than trying to make it up at dinner when you're already sated. Aim for 30–40 g per meal across 3–4 meals.
Do older adults need more protein?+
Yes. Adults over 60 develop anabolic resistance — they need more protein per meal to trigger the same muscle protein synthesis response. The PROT-AGE consensus recommends a minimum of 1.0–1.2 g/kg for healthy older adults, and 1.2–1.5 g/kg for those who are losing weight or recovering from illness. If you're 60+, treat the top of the range in this calculator as the floor, not the ceiling.
Will high protein damage my kidneys?+
In adults with healthy kidney function, protein intakes up to 2.0–2.4 g/kg have been studied in athletes and dieters for years without evidence of kidney harm. The concern applies specifically to people with pre-existing chronic kidney disease — if that's you, talk to your provider before increasing protein and don't use this calculator as a substitute for personalized medical advice.
What about resistance training?+
Protein gives muscle the raw material; resistance training gives it the reason to stay. Adults losing weight on a GLP-1 should pair high protein with 2–3 strength sessions per week. The combination consistently preserves more lean mass than either intervention alone — that's the strongest evidence-based lever you have.