Alex Gonzalez

Endocrinologist, ECNU, PR 🇵🇷 , Attending Physician, Clinical Researcher Endo#fulltimedreamer#learner

[Michael Albert, MD @MichaelAlbertMD]

“25–40% of weight loss is lean muscle” is not accurate.

What those analyses (STEP, SURMOUNT) actually report is loss of lean mass on DEXA—and that is not the same thing as skeletal muscle.

DEXA divides the body into:
🔹Fat mass
🔹Bone
🔹Lean soft tissue

That “lean” bucket includes water, glycogen, organs, connective tissue, and muscle. It is highly dynamic and shifts with caloric restriction, hydration, and glycogen depletion.

So when you see “25–40% lean mass loss,” what you’re really seeing is: ➡️ fat-free tissue change—not isolated muscle loss

If you want to measure actual skeletal muscle, you need CT or MRI (cross-sectional area, muscle volume, etc.).

And here’s the key point:
There is no consistent CT/MRI evidence showing that GLP-1–based therapies cause disproportionate skeletal muscle loss relative to expected weight loss physiology.

What we do know:
🔹All weight loss (diet, surgery, pharmacotherapy) includes some lean/FFM reduction
🔹The ~25–40% range is well-described baseline physiology, not a GLP-1-specific signal
🔹The dominant effect remains preferential fat mass loss with significant metabolic benefit

So this isn’t a drug-specific muscle-wasting phenomenon.
It’s a misinterpretation of what DEXA actually measures.

If we’re going to have strong opinions here, we should at least be precise about the difference between: lean mass, fat-free mass, and skeletal muscle

Because those are not interchangeable terms—and treating them like they are leads to bad conclusions.

[Alex Gonzalez @Apyg]

@BoWang87 Wow

[Alex Gonzalez @Apyg]

@scottisaacsmd Thank you for coming!!! Hope to see you again back at PR!

[Alex Gonzalez @Apyg]

@scottisaacsmd Advancing MASLD/MASH care at SPED PR 🇵🇷

[Alex Gonzalez @Apyg]

⁦@JaimeAlmandoz⁩ lecture on Amylin Based Therapies for Obesity and T2Dm #SPEDpR

[Alex Gonzalez @Apyg]

@JaimeAlmandoz @RodolfoJGalindo on a Q&A session . #SPEDPR 🇵🇷

[Alex Gonzalez @Apyg]

@RodolfoJGalindo at Sped PR on Glucagon Based therapies .

[Darren Cahill @darren_cahill]

Possessed every quality in an athlete that you want for your own kids to try & emulate

Kindness, respect, hard-working, loyal, generous, belief & a willingness to fight for every single point. A role model

An inspiration to every generation & all-time legend

Well done, Rafa 👏

[Wimbledon @Wimbledon]

Forever a champion.

#Wimbledon | @RafaelNadal

[Alex Gonzalez @Apyg]

@JaimeAlmandoz @TewksRD @MarsApovian @DrAngelaFitch @drard @tomwadden @KadieVanderman Excellent article ! For me, a change in my clinical practice!

[Alex Gonzalez @Apyg]

@RodolfoJGalindo @TheEndoSociety Excellent Program!!!

[Alex Gonzalez @Apyg]

The End of an excellent Weekend !!! Thanks to @drricardocorrea @robertwermers @JaimeAlmandoz and all the other excellent speakers!!! #PREndoMeeting 🇵🇷

[Jaime Almandoz, MD MBA FTOS @JaimeAlmandoz]

Great 🇵🇷Endo Society Session with Drs Ryan & Arslanian. Congrats to @Apyg and SPED!
👉Outcomes of obesity treatment should focus on health and not weight
👉Don’t ignore high rates of obesity and complications in adolescents
👉Educate patients and peers on obesity to reduce stigma

[Alex Gonzalez @Apyg]

Long term weight maintenance!! Recognizing multiple factors is important! @JaimeAlmandoz #PREndoMeeting 🇵🇷

[Alex Gonzalez @Apyg]

Thanks to @RangaswJ for the Amazing Lecture on CKM! 🇵🇷 #PREndoMeeting

[Alex Gonzalez @Apyg]

PR 🇵🇷 Endo Meeting!

[Alex Gonzalez @Apyg]

Excellent conference by @AgostoSarimar at PR 🇵🇷 #advancethyroidcancermanagement

[Prof. Feynman @ProfFeynman]

Teach your children how to think, not what to think.

[Luigi Gatto @gigicat7_]

Rafael Nadal on Clay | Unreal Dominance

Davis Cup 100%
Roland-Garros 97.5%
Barcelona 94%
Monte-Carlo 92%
Rome 89.6%
Hamburg 89%
Madrid: 82%
Best of 3: 89%
Best of 5: 98%
5th set: 100%
After winning 1st set 97.5%
Outdoor 91%
Indoor 100%
Overall: 91%

🤯

[Alex Gonzalez @Apyg]

Me!