Can someone explain the reason Reta is better for preserving lean muscle mass?

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amosmylove

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Hey there. I am taking Tirz and happy with it outside of pretty extreme fatigue. My husband wants to start a glp1 type peptide and I was thinking Reta might be better for him. I am fairly unfamiliar outside of reading tidbits here and there about many preferring Reta and noting it is better for preserving lean muscle mass. What is the mechanism in action in Reta that allows for this? I mentioned it to my husband and he thought there must be some sort or testosterone/hgh effect but I said I didn't think so. The way I was explaining it to him wasn't cutting it. I told him to research it himself but he doesn't deep dive on the internet like I do so I feel like his info gathered will be limited and AI biased.
 
Retatrutide is a triple agonist of GLP-1, GIP, and glucagon receptors. Semaglutide acts only on GLP-1; tirzepatide on GLP-1 and GIP. The glucagon component is the "extra" ingredient of retatrutide and is mechanistically responsible for the potential body composition benefits. This is counterintuitive because glucagon is classically associated with protein catabolism—and in fact, that is one of the drug's theoretical risks.

The relative preservation of lean mass with retatrutide does not stem from a direct "anti-catabolic" property, but rather from a redesign of the energy substrate balance during caloric deficit, mediated by the glucagon component. With access to more energy via thermogenesis and lipolysis, the body relies less on muscle as fuel. The true magnitude of this advantage over semaglutide and tirzepatide
 
Omxxl said:
Retatrutida es un agonista triple de los receptores GLP-1, GIP y glucagón. Semaglutida actúa únicamente sobre GLP-1; tirzepatida, sobre GLP-1 y GIP. El glucagón es el componente adicional de retatrutida y es el responsable, desde el punto de vista mecanístico, de los posibles beneficios en la composición corporal. Esto resulta contraintuitivo, ya que el glucagón se asocia clásicamente con el catabolismo proteico, y de hecho, este es uno de los riesgos teóricos del fármaco.

La preservación relativa de la masa magra con retatrutida no se debe a una propiedad "anticatabólica" directa, sino más bien a una reorganización del equilibrio de sustratos energéticos durante el déficit calórico, mediada por el glucagón. Al tener acceso a más energía mediante la termogénesis y la lipólisis, el cuerpo depende menos del músculo como combustible. La verdadera magnitud de esta ventaja sobre sema y tirze
Thank you for spelling this out for me. This was my understanding as well but you explain it so much better. Appreciate you!
 
If you also add testosterone and HGH, you have an incredible trio; I'm currently using that.
 
Either way he has to get enough protein and lift heavy things to not lose muscle.

Losing weight and lifting may improve Test in the long run.
 
Reta differs from Tirza due to the glucagon controlling action. Glucagon is the antagonist of insulin. Insulin removes glucose from the blood and converts it into fat in adipocytes. Glucagon acts on the liver to get it to convert glycogen into glucose. Now glycogen is also stored in muscle as well and that's the source of the catabolic activity mentioned earlier. Either way, studies show that reta-derived weight loss is about 60-80% fat loss and about 20-40% lean mass loss and this is better than pretty much everything else out there. Now, if you do sufficient resistance training and gobble enough protein, you will remain with fat loss and as little lean muscle loss as possible.

On reta, the action of glucagon could prevent muscle loss by not forcing muscle breakdown into glucose through gluconeogenesis. Replenishing the muscle lost through IGF-1/mTor action seems to be the counter. That's plausibly why those doing TRT with Reta seem to get the best results.
 
My understanding is like Omxxl said, GCGR signaling makes the liver work to produce alternate energy sources vs eating mucle.

I’m on TRT, take Reta, have an IGF Z Score of +1.4, and take HMB-FA.

In 54 days I lost ~18.7lb (7%) with ~.5lb of that being muscle according to my last two DEXA scans.

I’m looking forward to my next DEXA to see how things have progressed…. I’ll be getting another next month, another ~20lb down from my last scan.
 
I would also add that this mechanistically is pretty mild from the published data.

It gets this reputation more from bro culture using reta, additionally because the hunger suppression is not very strong it is easier to hit your macro goals and actually eat compared to tirz.
 
Yeah the weaker appetite suppression compared to Tirza could be turned into a boon. Food noise is definitely a problem, yet, the ability to hit your nutritional goals to preserve muscle is more valuable. The loss of too much muscle could render the weight loss moot due to the difficulty in keeping the weight off later.
 
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