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Regarding number 6, I’m glad the author is happy with her results so far. It’s important to note that because of the effect of GLP-1 inhibitors on lean muscle mass, it’s unlikely that they are the free lunch we’re hoping for: https://peterattiamd.com/the-downside-of-glp-1-receptor-agonists/

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I just read the Attia and, from what I can understand, the evidence in the article is if anything more positive findings about GLP-1 for adults with overweight or obesity. Attia is concerned here with lean body mass and body composition: "drugs designed to treat obesity are only beneficial if they can improve body composition in addition to body weight."

From what we know (which is limited because "Investigations into body composition changes on GLP-1 agonists are thus limited and likely underpowered") GLP-1 agonists do in fact improve body composition: "Indeed, despite the high lean mass losses, the proportion of lean mass to total body mass still increased in STEP 1 patients by an average of roughly 3% and in SUSTAIN 8 patients by an average of just over 1%."

It sounds like he's most worried about lean mass for healthy-weight individuals, which, fair enough: "However, GLP-1 agonists have also grown in popularity as a weight loss drug among those without obesity, a trend I find somewhat disconcerting." The note of caution on sarcopenic obesity also seems apt.

But yeah, it sounds like all the data in the Attia is actually just good news about GLP-1 inhibitors for overweight or obesity. Am I missing something?

Other question and point:

-is Attia suggesting that losing a lot of weight with GLP-1 inhibitors might affect lean body mass more than losing a lot of weight by good old calorie restriction? I take it that losing lean body mass is always a risk of losing weight, right? Genuine questions, I don't know

-this thread seemed optimistic about mitigating risks of lean muscle loss with high-protein diet and strength training https://twitter.com/MichaelAlbertMD/status/1627328086504087553?s=20

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[Much of this comes from lots of podcast listening, so hopefully even if some details are missing, the gestalt is correct] So for context, Attia has been rather pro-GLP-1 for years, had many patients on it, and has also been quite pro-fasting for even longer. Recently, after seeing plenty of DEXA scans from his patients (and I think himself) that have shown more than negligible muscle mass loss, and reviewing literature on the topic, he has pulled back somewhat on both the fasting and GLP-1. The gist of the importance of muscle mass is both its function as a metabolic organ and also functional ability, especially as you get older, and basically lean muscle mass loss is more deleterious than is probably discussed, at least in the commonplace way people discuss the benefits of weight loss. So there is very likely some population that receives net benefit from a GLP-1 induced weight loss, even with lean muscle mass loss, there is also very likely a not-insignificant portion of the population where there is questionable benefit or even harm. But FDA guidance is to not look at body composition, so studies better defining those populations are underpowered or indeed may only exist as subgroup analyses in other studies. Meanwhile semaglutide is literally being called a miracle drug is mass media. Absent any information about the health history of Rosie Campbell, I can't even make a guess as to which population group she is in, though if she's in the overweight/obese category she's likely receiving a net benefit. And shouldn't be judged for using a pill to receive that benefit. I would be a little cautionary about her guess that she might like to be on it for the rest of her life, as once she achieves a healthy weight, she might not be in the benefit-receiving population anymore. And to your questions, lean muscle mass loss is indeed always a concern in diet/exercise related weight loss as well. And like you mention, in both weight loss strategies appropriate protein intake will likely mitigate the that (I wonder if the people on semaglutide would find it more difficult to find take it in because of their appetite changing?). But what cannot be overstated, is being completely ignored, and I think is one of the real issues of the "magic weight loss pill" idea is that *there are benefits to good diet and exercise other than weight loss*. Metabolic, cardiovascular, functional, mental, the list goes on, and while a few of these things may improve in a semaglutide lifestyle, not all of them will, and so all I really want to highlight is that for a lot of people, more needs to be considered than "this made me lose weight really easily".

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