Free test · 10 questions · 2 minutes
Am I losing muscle with Ozempic or Mounjaro?
With a GLP-1, the number on the scale goes down, but it does not tell you what you are losing: fat or muscle. Answer 10 questions about your strength, what you eat, and how you feel, and we will tell you what to watch. Also applies to Wegovy, Saxenda, or Rybelsus.
Test: are you losing muscle?
Is it harder than before to climb several flights of stairs?
Does carrying groceries or bags take more effort than before?
Is it harder to open jars or lids that you used to open easily?
Do you have less energy or feel more tired than before starting the medication?
Do you include protein (eggs, meat, fish, legumes or dairy) in every main meal?
How many days a week do you skip a meal because you are not hungry?
Do you do any strength training, with or without a gym?
Are you losing weight very quickly (more than 1 kg per week on an ongoing basis)?
Do your clothes fit differently around your arms or legs, not just your waist?
Have you noticed more hair loss over the last few months?
This test is for guidance only. It is not a diagnostic test and does not replace an assessment by a health professional.
Your next step
Know what you are losing and help protect your muscle
Complete the test and we will suggest where to start. In the meantime, here are three ways to continue.
Free · by email
Guide: Your first 16 weeks on a GLP-1
What to eat with each dose increase, how much protein you need, and how to build strength without a gym, with a 7-day menu.
Data controller: Alimmenta Tu Vida, S.L. Purpose: to send you the guide you requested and, only if you tick the second box, nutrition tips by email on that topic. Legal basis: your consent, which you can withdraw at any time. Recipients: we do not share your data with anyone; emails are sent by Resend as our data processor. Rights: access, rectification, erasure, objection, restriction and portability at [email protected]. More information in our privacy policy.
First appointment
We measure your fat, muscle, and strength
€65 45 min · in Barcelona or online
Body-composition and strength assessment in the clinic, with protein and meal guidance tailored to your treatment.
Book your first appointmentPrefer to call? 93 218 95 32
GLP-1 programme
Support through all five stages
€550 package of 10 appointments · €55 each
Fat and muscle measurements every 6 weeks during active weight loss, follow-up after each dose increase, and a plan for stopping treatment.
View the programmeWe do not prescribe medication or change your dose: your doctor makes those decisions.
Is muscle loss normal with a GLP-1?
Some muscle is always lost during weight loss, with or without medication. With Ozempic, Wegovy, or Mounjaro, the proportion is similar to that seen with dieting, but because substantial weight can be lost, the amount may be significant: studies found that between one quarter and nearly two fifths of the weight lost was lean mass [4][5]. With 20 kg of weight loss, that is 5 to 8 kg.
The risk is higher if you are over 60, already had low muscle mass, eat very little, or do not do strength exercise. That is why scientific societies recommend taking care with protein intake and doing strength exercise throughout treatment [3][8].
How to tell whether you are really losing muscle
This test looks at indirect signs. Measurements are needed to know for sure. In the clinic, we use three simple tests and repeat them every few weeks to track changes:
Body composition
How much of your body weight is fat and how much is muscle, not just your weight in kilos.
Handgrip strength
Using a handgrip dynamometer: less than 27 kg for men or 16 kg for women indicates low strength [1].
Chair-rise test
How long it takes you to stand up 5 times in a row without using your hands: more than 15 seconds indicates low strength [1].
What you can do to help prevent muscle loss
- Eat enough protein, between 1.2 and 1.6 g per kilogram of body weight per day, spread across all meals [3]. Calculate your needs.
- Do strength exercise several days a week, with or without a gym: climb stairs carrying a load, do chair squats, or use resistance bands [3].
- Do not skip meals even if you are not hungry: have small meals at set times, starting with protein.
- Watch your rate of weight loss: if you lose more than 1 kg a week for several weeks, discuss it with your doctor.
This test does not replace your doctor
It is for guidance only and is not a diagnostic test. If you experience marked weakness, dizziness, significant hair loss, or very rapid weight loss, discuss it with your doctor. Your doctor always decides the medication dose.
Sources and how we calculated it
The questions in this test are based on European sarcopenia criteria and published studies on GLP-1 medicines. The sources are listed in the order they are cited.
- Cruz-Jentoft AJ, Bahat G, Bauer J, Boirie Y, et al. Sarcopenia: revised European consensus on definition and diagnosis (EWGSOP2). Age Ageing. 2019;48(1):16-31. doi:10.1093/ageing/afy169
- Malmstrom TK, Morley JE. SARC-F: a simple questionnaire to rapidly diagnose sarcopenia. J Am Med Dir Assoc. 2013;14(8):531-532. doi:10.1016/j.jamda.2013.05.018
- Mozaffarian D, Agarwal M, Aggarwal M, Alexander L, 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. Am J Clin Nutr. 2025;122(1):344-367. doi:10.1016/j.ajcnut.2025.04.023
- Look M, Dunn JP, Kushner RF, Cao D, et al. Body composition changes during weight reduction with tirzepatide in the SURMOUNT-1 study of adults with obesity or overweight. Diabetes Obes Metab. 2025;27(5):2720-2729. doi:10.1111/dom.16275
- Wilding JPH, Batterham RL, Calanna S, Van Gaal LF, et al. Impact of semaglutide on body composition in adults with overweight or obesity: exploratory analysis of the STEP 1 study. J Endocr Soc. 2021;5(Suppl 1). doi:10.1210/jendso/bvab048.030
- Butsch WS, Sulo S, Chang AT, Kim JA, et al. Nutritional deficiencies and muscle loss in adults with type 2 diabetes using GLP-1 receptor agonists: a retrospective observational study. Obesity Pillars. 2025;15:100186. doi:10.1016/j.obpill.2025.100186
- Lanehart MH, Zinn Z, Beatty CJ. Association between GLP-1 receptor agonists and nonscarring hair loss: a population-based, propensity score matched cohort analysis. Arch Dermatol Res. 2026;318. doi:10.1007/s00403-026-04603-w
- Dobbie LJ, Tolvanen L, Alves D, Baker JL, et al. Nutritional, functional, and psychological considerations for incretin-based therapies in adults: an EASO, EFAD, and ECPO Consensus Statement. Lancet Diabetes Endocrinol. 2026;14(9):754-777. doi:10.1016/S2213-8587(26)00122-1
What supports each question and how the score works
- Questions 1–3 (stairs, bags, jars): signs related to strength. Climbing stairs and carrying weight are items in the SARC-F questionnaire [2], which the European EWGSOP2 consensus recommends for screening; opening jars is a hand-strength task, the test used by EWGSOP2 [1].
- Question 4 (energy or tiredness): a non-specific symptom that may be related to eating very little; in a cohort of more than 460,000 adults taking GLP-1 medicines, 12.7 % developed a new nutritional deficiency after 6 months [6]. This is an Alimmenta criterion.
- Questions 5–7 (protein, skipped meals, strength): habits that protect muscle according to the joint scientific-society guidance [3].
- Question 8 (more than 1 kg per week): weight-loss-rate threshold chosen by Alimmenta; it is not a figure from the cited sources.
- Question 9 (clothing fit around arms and legs): an Alimmenta clinical observation, without a direct source.
- Question 10 (hair loss): reported more often with GLP-1 medicines in a matched population cohort [7].
- Scoring. Each answer adds 0, 1, or 2 points (0–20). The ranges 0–6 low risk, 7–13 keep an eye on it, and 14–20 arrange an assessment soon are Alimmenta criteria, not a validated questionnaire, and await validation by the Technical Director. The test is for guidance; only measurements can confirm muscle loss.
Review date: 26/09/2026Reviewed by Juana Mª González, Clinical Director (Registration No. CAT000921)
What people who have been to the clinic say
5.0 out of 5 · 295 reviews on Google
Después de 5 meses y habiendo superado el objetivo de pérdida de peso que habíamos fijado, agradezco a Sandra su asesoramiento. No es sólo una "dieta", es entender los motivos por los que nos llevan a donde estamos y aprender
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a alimentarnos en la edad biológica y en el estado emocional que vives. Siempre pensé que me alimentaba bien y al principio fue un choque el cambio de alimentación que tuve que realizar, pero desde el principio lo pude combinar perfectamente con mi vida social y esto ha supuesto un plus de empuje para no abandonar las pautas. Estoy agradecida y animos a los indecisos/as a que realicen su acompañamiento …
Carmen
Descubrí Alimmenta porque buscaba nutricionistas en el Maresme y me guíe por sus buenas reseñas, totalmente acertado! Comencé con Sandra hace dos meses y medio y mi experiencia está siendo muy satisfactoria. Me ha ayudado mucho con la planificación de
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mi dieta, estoy aprendiendo a comer de forma más equilibrada y con hábitos que puedo incorporar a mi día a día de manera duradera. Verdaderamente los resultados están siendo buenos, estoy viendo un cambio notable en mi recomposición corporal. Recomiendo totalmente a Sandra como nutricionista a cualquier persona que quiera bajar de peso sin pasar hambre y adquiriendo buenos hábitos alimenticios, que al fin y al cabo es lo más …
Alicia
Molt content d'haver-me trobat amb la Sandra, des de la primera visita tot ha sigut un procés que ha anat a millor, totes les sessions amb ella són un aprenentatge, es nota que sap el que fa i del que
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parla, i aplicar-ho en el dia a dia m'ha fet crear un estil de vida i baixar de pes ben ràpid, només tinc paraules bones per ella, recomanable 100%
Sergi
Estoy encantada con Berta, muy buena profesional y me ha enseñado a comer, así es muy fácil perder peso. En ningún momento he pasado hambre, todo al contrario. Es aprender la filosofía de la nutrición. Mil gracias
Manuela
La Sandra ha estat una gran ajuda, molt honesta i realista en tot moment. Al seu costat he après a menjar correctament sense deixar de gaudir del menjar, alhora que he pogut perdre uns quants quilos i, sobretot, el més
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important: sentir-me molt millor. Moltes gràcies per tot, i continuem!
Míriam
Berta m’ha canviat la vida a Molt millor las mevas intolerancias las ha controlat i amb las sevas pautas d’alimentacio m’he aprimat 2 tallas. Salut i benestar. Gran profesional!
Merchi
Vaig començar a anar amb la Sandra amb una idea molt clara: baixar pes. Però el que he guanyat va molt més enllà d’això. Gràcies a ella he entès millor com funciona el que menjo i com puc alimentar-me de
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manera més conscient i equilibrada. Sobretot, m’ha ajudat a veure que la meva relació amb el menjar no era sana: sovint menjava per tapar emocions, i això després em generava culpabilitat, entrant en un bucle difícil de trencar. Amb el seu acompanyament, he aconseguit millorar molt aquesta relació. Encara hi ha moments (soc humà 😅), però ara tinc més consciència i eines per gestionar-ho sense culpa. Això m’ha aportat molta …
Miki
Frequently asked questions about muscle and GLP-1 medicines
Do Ozempic or Mounjaro cause muscle loss?
Yes, some muscle can be lost, as with any form of weight loss. Studies found that between one quarter and nearly two fifths of the weight lost was lean mass. Adequate protein and strength exercise can reduce this proportion.
How can I tell if I am losing muscle rather than fat?
The scale cannot tell you. Body composition and strength need to be measured, for example with a dynamometer or by timing how long it takes you to stand up from a chair 5 times. Everyday signs, such as getting more tired on stairs, may raise suspicion.
What can I do to help prevent muscle loss while taking a GLP-1?
Eat between 1.2 and 1.6 g of protein per kilogram of body weight per day, spread across meals; do strength exercise several days a week and do not skip meals even if you are not hungry.
Is “Ozempic face” caused by muscle loss?
It is mainly linked to rapid weight loss, which reduces facial fat volume. Losing weight at a reasonable rate and getting enough protein may help. Read our guide to Ozempic face.
Can this test diagnose muscle loss?
No. It can help you decide whether to monitor possible muscle loss or request an assessment. Only measurements of body composition and strength can confirm it.
Keep reading
- GLP-1 protein calculator
Your daily protein target, spread across meals.
- Protein and muscle while taking a GLP-1
The complete guide to protecting your muscle mass.
- Ozempic face
Why your face changes with rapid weight loss and what you can do.
- GLP-1 medicines: everything you need to know
How they work, what you lose, and what happens when you stop.
- Ozempic
What it is, its price in Spain, and how to eat while taking it.
- Wegovy
Approved uses, doses, and nutrition.
- Mounjaro
Tirzepatide: doses, price, and what to eat.
Make sure what you lose is fat—and keep it off
We support you from your first dose until one year after stopping treatment, at our Barcelona clinic or online. 4.9 on Google · 5.0 on Doctoralia · 2,072 reviews.