Free tool · GLP-1 nutrition
How much protein do you need on a GLP-1?
Put your numbers in. Your target updates as you type.
Your numbers
Are you taking a GLP-1?
What that looks like on a plate
This is education, not medical advice
Protein targets have to be individualized. Higher protein intake may be inappropriate if you have chronic kidney disease, liver disease, or are pregnant or breastfeeding. Talk to your prescriber or a registered dietitian before changing your intake, and ask for a body-composition measurement if one is available to you.
Your daily protein target
Reasonable range 70–105 g per day
About 30 g at each of three meals
The published range for adjusted weight is 1.0 to 1.5 g per kg. You are set at 1.40 g per kg of your 153 lb adjusted weight, based on how much you have to lose, your training, and your age.
Off a GLP-1, the same body would be aiming for about 90 g. The extra 7 g covers the faster loss and the smaller appetite.
There is no single agreed formula
Some guidance bases protein on your ideal weight, other guidance on the weight you are today. Neither is wrong, and the two can be far apart. For weight loss on a GLP-1, clinical nutrition guidance uses adjusted weight, so that is the default here. Tap to compare.
Against the standard adult RDA
The 0.8 g/kg RDA would be 80 g
The 0.8 g/kg RDA is the minimum to avoid deficiency in an adult who is not losing weight. It was never meant as a target during weight loss.
You have 55 lb to lose, or 25% of your body weight. The larger the total loss, the more of it tends to come from lean tissue, so a bigger gap moves your target up inside its range.
How your number is built
Why protein matters more on a GLP-1
You eat less, so protein slips first
These medications reduce appetite and slow digestion, so your total intake falls. Food aversion and changes in taste are common in the early weeks, and protein-dense food is often the first thing that stops appealing.
Some of the weight you lose is muscle
In the semaglutide and tirzepatide trials, fat-free mass accounted for 25% to 39% of the weight participants lost. Reviewing those trials, Mechanick and colleagues estimate at least 10% of muscle mass lost over 68 to 72 weeks.
The more you have to lose, the more is at stake
A systematic review of significant weight loss found that the share coming from fat-free mass rises as the total loss gets larger. Researchers attribute the muscle loss seen on these medications to the amount of weight lost rather than to the drug itself.
Protein is only half of it
Strength work is what tells your body to keep the muscle. The Physical Activity Guidelines for Americans ask for muscle-strengthening activity on two or more days a week, alongside 150 to 300 minutes of moderate activity.
Sources
10 references
- Mechanick JI, Butsch WS, Christensen SM, Hamdy O, Li Z, Prado CM, Heymsfield SB. Strategies for minimizing muscle loss during use of incretin-mimetic drugs for treatment of obesity. Obesity Reviews. 2025;26(1):e13841. doi:10.1111/obr.13841. Open access. Source of the STEP 1 and SURMOUNT-1 body-composition figures, the ideal- and adjusted-body-weight conventions, and the 60 g/day floor.
- Prado CM, Phillips SM, Gonzalez MC, Heymsfield SB. Muscle matters: the effects of medically induced weight loss on skeletal muscle. The Lancet Diabetes & Endocrinology. 2024;12(11):785–787. doi:10.1016/S2213-8587(24)00272-9.
- 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. The American Journal of Clinical Nutrition. 2025;122(1):344–367. doi:10.1016/j.ajcnut.2025.04.023. A corrigendum was published in 2026.
- Cava E, Yeat NC, Mittendorfer B. Preserving healthy muscle during weight loss. Advances in Nutrition. 2017;8(3):511–519. doi:10.3945/an.116.014506.
- Dekker IM, van Rijssen NM, Verreijen A, et al. Calculation of protein requirements: a comparison of calculations based on bodyweight and fat free mass. Clinical Nutrition ESPEN. 2022;48:378–385. doi:10.1016/j.clnesp.2022.01.014.
- Wilding JPH, Batterham RL, Calanna S, et al. Once-weekly semaglutide in adults with overweight or obesity (STEP 1). New England Journal of Medicine. 2021;384(11):989–1002. doi:10.1056/NEJMoa2032183.
- Jastreboff AM, Aronne LJ, Ahmad NN, et al. Tirzepatide once weekly for the treatment of obesity (SURMOUNT-1). New England Journal of Medicine. 2022;387(3):205–216. doi:10.1056/NEJMoa2206038.
- Chaston TB, Dixon JB, O'Brien PE. Changes in fat-free mass during significant weight loss: a systematic review. International Journal of Obesity. 2007;31(5):743–750. doi:10.1038/sj.ijo.0803483. The source for the share of weight loss coming from fat-free mass rising with the size of the loss.
- Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. National Academies Press, 2005. doi:10.17226/10490. Source of the 0.8 g/kg RDA.
- US Department of Health and Human Services. Physical Activity Guidelines for Americans, 2nd edition, 2018. health.gov.
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