Stacking a GLP with metformin - worth trying for fat loss?

Cluni0n

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Hi everyone, i am talking things over with my doctor to work out which medication suits me best. I am significantly overweight (224lbs, 5'4F) with a hiigh HOMA score (7.9), though my fasting glucose, A1C, cholesterol, no fatty liver and the rest of my test results all sit in the normal ranges (perks of carrying a ton of muscle mass tho). I have been reading a little about combined therapy and it seems to give good results: you lose less muscle mass, a lower metformin dose means fewer side effects, ozempic doses stay low, and it hits different hormonal mechanisms. I found that genuinely interesting, so i would like to hear from anyone who has tried this method before - sharing your experience would be great, thanks! 🙂
 
I take Jardiance from India alongside my GLPs sometimes. No hypoglycemia issues. (I cycle Jardiance because the extra peeing gets tiring. So i hold off and take it when i am on a GH peptide as well, to help keep fluid retention down on GH peptides.)
 
Cluni0n said:

Hi everyone, i am talking things over with my doctor to work out which medication suits me best. I am significantly overweight (224lbs, 5'4F) with a hiigh HOMA score (7.9), though my fasting glucose, A1C, cholesterol, no fatty liver and the rest of my test results all sit in the normal ranges (perks of carrying a ton of muscle mass tho). I have been reading a little about combined therapy and it seems to give good results: you lose less muscle mass, a lower metformin dose means fewer side effects, ozempic doses stay low, and it hits different hormonal mechanisms. I found that genuinely interesting, so i would like to hear from anyone who has tried this method before - sharing your experience would be great, thanks! 🙂
Metformin brings glucose and A1C down, but it usually does little for weight loss. Some people do report stomach issues on it, though those are generally milder than with semaglutide.

If weight loss is the goal, then frankly semaglutide or tirzepatide on their own are superior. Metformin is for glucose control, and it looks like you do not need that.

Muscle loss on GLP1 is overblown, provided your nutrition is decent (read: protein) and you do some physical activity. Bear in mind that apparent muscle reductions come partly from less fat accumulating inside the muscle, so the muscle loses some volume. CT measurement confirmed this. In studies, much of the lean mass loss actually comes from liver mass and other internal organs, which shrink along with systemic inflammation and fat storage.
 
Yeah, taking metformin for prediabetes before i moved to GLPs was essentially an exercise in diarrhea for me. On its own it gave minimal weight loss, if any. So it would be better at maintaining weight than losing it.

Moving from Ozempic to Zepbound (or grey tirz) would beat adding metformin by a long way, for both weight loss and health markers.
 
Cluni0n said:

Hi everyone, i am talking things over with my doctor to work out which medication suits me best. I am significantly overweight (224lbs, 5'4F) with a hiigh HOMA score (7.9), though my fasting glucose, A1C, cholesterol, no fatty liver and the rest of my test results all sit in the normal ranges (perks of carrying a ton of muscle mass tho). I have been reading a little about combined therapy and it seems to give good results: you lose less muscle mass, a lower metformin dose means fewer side effects, ozempic doses stay low, and it hits different hormonal mechanisms. I found that genuinely interesting, so i would like to hear from anyone who has tried this method before - sharing your experience would be great, thanks! 🙂
As an ex-diabetic i have used both, and if you really want metformin, use it only as a senolytic. In your case though, the anti-gluconeogenesis effect might be useful. I use it myself every 3 days to help with glycogen replenishment in the muscles.
 
Metformin can help with weight loss by itself. It is not normally prescribed for that purpose specifically, and results vary, but claiming it is not associated with weight loss is wrong. If you are weighing up both, there is no harm in asking your doctor to write prescriptions for both.

If you do decide to run both, starting them at the same time is not something i would recommend, since GI side effects are very common with each and you probably do not want your first week of treatment to be the maximum side effects. Starting one and stabilising before adding the other makes far more sense to me. Even if you are unsure whether you will take it, metformin is an old generic and dirt cheap, so there is no harm in getting a prescription filled just so the option is there later (rather than having to go back to your doctor). That gives you plenty of time to ease into a GLP and read up further on metformin, instead of feeling under the gun the way you may right now.

I dropped metformin myself once i started a GLP (despite having minimal side effects on it), and from what you have said i am not sure there is a strong reason to add it to the GLP. That goes double if metformin gives you any significant GI side effects.
 
Metformin produced 2.1 percent weight loss after 2+ years :

the DPP Outcomes Study paper on long-term weight loss with metformin

A recent systematic review and meta-analysis reported an average weight loss of 1.1 kg with metformin used for varying periods (18). In the DPP/DPPOS, the metformin group had an average weight loss of 2.1% after 2 years, and remarkably, the group maintained ~2% weight loss for the next 10 years (19). Taken together, it appears that long-term metformin treatment is associated with an average ~1–2% weight loss when assessed among all of those given the drug.

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Gemini said:


MedicationMechanismAverage Weight Loss (%)Trial DurationMetforminBiguanide~2.1%~3 yearsJardianceSGLT2 Inhibitor~3.0%~3.1 years (median)SemaglutideGLP-1 RA~14.9%68 weeks (~1.3 years)TirzepatideGLP-1/GIP RA~20.9%72 weeks (~1.4 years)RetatrutideTriple Agonist~24.2%48 weeks (~11 months)





817c5ead929e9e18cf866743a15d117dea7937b8221bfac5be4a20b3036bb620.webp


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The metformin side effects were too much for me. It gave me muscle cramps that made my daily runs uncomfortable. I still have a couple of years worth left over from when i was struggling with high blood sugar.

There is recent research suggesting metformin cancels out some of the aerobic exercise benefits in diabetics.

https://share.google/ZXsfaOQYOm1iwwuNu
 
Calm Logic said:

Metformin produced 2.1 percent weight loss after 2+ years :

the DPP Outcomes Study paper on long-term weight loss with metformin

A recent systematic review and meta-analysis reported an average weight loss of 1.1 kg with metformin used for varying periods (18). In the DPP/DPPOS, the metformin group had an average weight loss of 2.1% after 2 years, and remarkably, the group maintained ~2% weight loss for the next 10 years (19). Taken together, it appears that long-term metformin treatment is associated with an average ~1–2% weight loss when assessed among all of those given the drug.

Click to expand...

Gemini said:


MedicationMechanismAverage Weight Loss (%)Trial DurationMetforminBiguanide~2.1%~3 yearsJardianceSGLT2 Inhibitor~3.0%~3.1 years (median)SemaglutideGLP-1 RA~14.9%68 weeks (~1.3 years)TirzepatideGLP-1/GIP RA~20.9%72 weeks (~1.4 years)RetatrutideTriple Agonist~24.2%48 weeks (~11 months)





View attachment 244

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Is the 2.1% figure adjusted for placebo?
 
woundcarping said:

Calm Logic said:

Metformin produced 2.1 percent weight loss after 2+ years :

the DPP Outcomes Study paper on long-term weight loss with metformin

A recent systematic review and meta-analysis reported an average weight loss of 1.1 kg with metformin used for varying periods (18). In the DPP/DPPOS, the metformin group had an average weight loss of 2.1% after 2 years, and remarkably, the group maintained ~2% weight loss for the next 10 years (19). Taken together, it appears that long-term metformin treatment is associated with an average ~1–2% weight loss when assessed among all of those given the drug.

Click to expand...

Gemini said:


MedicationMechanismAverage Weight Loss (%)Trial DurationMetforminBiguanide~2.1%~3 yearsJardianceSGLT2 Inhibitor~3.0%~3.1 years (median)SemaglutideGLP-1 RA~14.9%68 weeks (~1.3 years)TirzepatideGLP-1/GIP RA~20.9%72 weeks (~1.4 years)RetatrutideTriple Agonist~24.2%48 weeks (~11 months)





View attachment 244

Click to expand...
Is the 2.1% figure adjusted for placebo?
Technically no, but the placebo group lost less than 0.1% [PubMed: 22442396]:

After 2 years, weight loss was 2.1 ± 5.7% in the metformin group compared with 0.02 ± 5.5% (P < 0.001) in the placebo group.

Click to expand...

The argument for metformin, and for stacking it with GLPs:

Gemini said:


  • The "Adherence" Factor: The 2.1% is a broad average. For participants who were highly adherent (consistently taking their prescribed dose), the mean weight loss was significantly higher at 3.5%.
  • The "Responder" Group: About 28.5% of the metformin group were "high responders," losing 5% or more of their body weight. These individuals were the most likely to maintain that loss for the full 15-year follow-up period.
  • Durability over Intensity: The study's main takeaway was that while metformin doesn't cause the massive initial drop seen with lifestyle changes (or modern GLP-1s), the weight lost is highly sustainable. Metformin users kept their weight off for 10–15 years, whereas lifestyle-only participants tended to regain weight over time.
Why this makes Metformin the top choice for "Stacking"​Because the study shows Metformin provides a durable "metabolic floor," it is often considered the best oral drug to pair with a GLP-1 for these reasons:

  1. Combating Resistance: If you hit a plateau on a GLP-1, the DPPOS data suggests Metformin helps by maintaining insulin sensitivity over the long haul, potentially "re-sensitizing" the body to weight loss.
  2. Maintenance Protocol: Given the high regain rates after stopping GLP-1s, the long-term safety and durability data from the DPPOS make Metformin a prime candidate for a "taper" or maintenance phase.
  3. Cost-Benefit Profile: Unlike SGLT2s or Contrave, Metformin is widely accessible and has the longest-running safety data (as evidenced by this 15+ year study) for weight management.

Click to expand...
 
A Dr i saw was a big fan of Glps; his line was to take the Glp, then use metformin to maintain.

I tried it before & lost no weight on it. It did help me sleep very well, and it eased pain
 
Plenty of things here are new to me - metformin being muscle sparing on a deficit, the stomach issues or diarrhea, using it as a senolytic. jardiance is another one i had never heard of, though at first glance it looks interesting, it makes you pee out sugar? So it seems i have a bunch of rabbit holes to go down.

Personally i used metformin years ago, for blood sugar control when i was heavier and starting HGH. It worked well enough i suppose - i can only assume it kept my blood sugar normal - and i had no noticeable side effects. I do not need it now, especially while taking reta; combining the two would drop blood sugar a lot.

Going by the bro science, you should try it. Metformin is cheap, safe and, as far as i knew until now, well tolerated. It is a low risk, high reward bet.
 
Cluni0n said:

Hi everyone, i am talking things over with my doctor to work out which medication suits me best. I am significantly overweight (224lbs, 5'4F) with a hiigh HOMA score (7.9), though my fasting glucose, A1C, cholesterol, no fatty liver and the rest of my test results all sit in the normal ranges (perks of carrying a ton of muscle mass tho). I have been reading a little about combined therapy and it seems to give good results: you lose less muscle mass, a lower metformin dose means fewer side effects, ozempic doses stay low, and it hits different hormonal mechanisms. I found that genuinely interesting, so i would like to hear from anyone who has tried this method before - sharing your experience would be great, thanks! 🙂
Honestly, a HOMA reading of 7.9 says a lot about insulin resistance, and that holds true even when fasting glucose and A1C both come back looking fine. Plenty of folks overlook this part of the picture, because the conversation tends to circle around the diabetes label itself, or around whether metformin deserves any place in a weight loss plan.

What your doctor is weighing up here is not really metformin's own fat-shedding power. The target is the insulin resistance your bloodwork is pointing at.

HOMA reads the balance between your fasting glucose and your fasting insulin. Glucose can sit in range while the body churns out far more insulin than it should just to hold it there. All of that extra insulin can stall fat loss, drive hunger and cravings in some people, and over the long haul move things toward prediabetes or metabolic dysfunction.

Which is why the usual complaint that metformin will not shift the scale on its own sort of sidesteps the reason it gets prescribed in a case like yours. The aim is usually better insulin sensitivity and less insulin production on your part.... not only chasing a number on the scale, but making weight loss something you CAN actually achieve.

And to be fair, thinking in terms of combination therapy is nothing unusual these days. Slower-dose GLP1s paired with metformin can sometimes:

attack insulin sensitivity from more than one direction

take the edge off appetite and keep you satisfied

let smaller doses work with fewer side effects along the way

give your metabolism a broader push in the right direction

protect lean tissue better, provided protein intake is adequate and you are lifting

Also, the muscle point you raised deserves more weight than it usually gets. A person carrying a good amount of muscle can keep glucose and A1C looking fine for years, simply because muscle soaks up glucose so effectively... even while resistance builds quietly underneath. That is exactly where fasting insulin and HOMA earn their keep in a clinical setting.

Those are good questions, and you are already looking past the idea of picking whichever drug drops weight fastest, which is really the conversation that matters over the long term with a HOMA that high.
 
Assuming both tirzepatide and semaglutide are on the table for you, I would lean tirzepatide. With a large amount of weight to lose, it simply performs better at that, and it usually comes with fewer side effects at the same time. Neither one leaves diabetes risk untouched - both cut it sharply - and since part of the thinking in your situation is preventing type 2 diabetes, my impression is that tirzepatide has the edge there too.

Metformin brings a modest amount of weight loss along with it, and it lowers diabetes risk as well, though nowhere near as much as the GLP drugs do. Pairing the two makes sense, but since both metformin and GLPs are notorious for gastrointestinal trouble, do not kick them off together.

Where tirz beats sema most clearly is in how much weight comes off over the long run.
 
Jfrick11 said:

Cluni0n said:

Hi everyone, i am talking things over with my doctor to work out which medication suits me best. I am significantly overweight (224lbs, 5'4F) with a hiigh HOMA score (7.9), though my fasting glucose, A1C, cholesterol, no fatty liver and the rest of my test results all sit in the normal ranges (perks of carrying a ton of muscle mass tho). I have been reading a little about combined therapy and it seems to give good results: you lose less muscle mass, a lower metformin dose means fewer side effects, ozempic doses stay low, and it hits different hormonal mechanisms. I found that genuinely interesting, so i would like to hear from anyone who has tried this method before - sharing your experience would be great, thanks! 🙂
Honestly, a HOMA reading of 7.9 says a lot about insulin resistance, and that holds true even when fasting glucose and A1C both come back looking fine. Plenty of folks overlook this part of the picture, because the conversation tends to circle around the diabetes label itself, or around whether metformin deserves any place in a weight loss plan.

What your doctor is weighing up here is not really metformin's own fat-shedding power. The target is the insulin resistance your bloodwork is pointing at.

HOMA reads the balance between your fasting glucose and your fasting insulin. Glucose can sit in range while the body churns out far more insulin than it should just to hold it there. All of that extra insulin can stall fat loss, drive hunger and cravings in some people, and over the long haul move things toward prediabetes or metabolic dysfunction.

Which is why the usual complaint that metformin will not shift the scale on its own sort of sidesteps the reason it gets prescribed in a case like yours. The aim is usually better insulin sensitivity and less insulin production on your part.... not only chasing a number on the scale, but making weight loss something you CAN actually achieve.

And to be fair, thinking in terms of combination therapy is nothing unusual these days. Slower-dose GLP1s paired with metformin can sometimes:

attack insulin sensitivity from more than one direction

take the edge off appetite and keep you satisfied

let smaller doses work with fewer side effects along the way

give your metabolism a broader push in the right direction

protect lean tissue better, provided protein intake is adequate and you are lifting

Also, the muscle point you raised deserves more weight than it usually gets. A person carrying a good amount of muscle can keep glucose and A1C looking fine for years, simply because muscle soaks up glucose so effectively... even while resistance builds quietly underneath. That is exactly where fasting insulin and HOMA earn their keep in a clinical setting.

Those are good questions, and you are already looking past the idea of picking whichever drug drops weight fastest, which is really the conversation that matters over the long term with a HOMA that high.


https://www.reddit.com/r/InsulinResistance/s/CEVZ5LekEG


A thread titled "6 months Metformin - weight down but HOMA up?"

e1aab7c6f4ddde73559859608f0347cea6038ed2f7f1641ccf130e2f18db7e28.webp


So that is one more argument for putting Zepbound/tirz ahead of the rest. Or possibly grey reta.

I never got a baseline fasting insulin number back then, but across a year my A1c came down from 6.1 to 5.3, and tirz on its own did most of that. Fasting insulin looks normal, even great, these days.
 
Calm Logic said:

Jfrick11 said:

Cluni0n said:

Hi everyone, i am talking things over with my doctor to work out which medication suits me best. I am significantly overweight (224lbs, 5'4F) with a hiigh HOMA score (7.9), though my fasting glucose, A1C, cholesterol, no fatty liver and the rest of my test results all sit in the normal ranges (perks of carrying a ton of muscle mass tho). I have been reading a little about combined therapy and it seems to give good results: you lose less muscle mass, a lower metformin dose means fewer side effects, ozempic doses stay low, and it hits different hormonal mechanisms. I found that genuinely interesting, so i would like to hear from anyone who has tried this method before - sharing your experience would be great, thanks! 🙂
Honestly, a HOMA reading of 7.9 says a lot about insulin resistance, and that holds true even when fasting glucose and A1C both come back looking fine. Plenty of folks overlook this part of the picture, because the conversation tends to circle around the diabetes label itself, or around whether metformin deserves any place in a weight loss plan.

What your doctor is weighing up here is not really metformin's own fat-shedding power. The target is the insulin resistance your bloodwork is pointing at.

HOMA reads the balance between your fasting glucose and your fasting insulin. Glucose can sit in range while the body churns out far more insulin than it should just to hold it there. All of that extra insulin can stall fat loss, drive hunger and cravings in some people, and over the long haul move things toward prediabetes or metabolic dysfunction.

Which is why the usual complaint that metformin will not shift the scale on its own sort of sidesteps the reason it gets prescribed in a case like yours. The aim is usually better insulin sensitivity and less insulin production on your part.... not only chasing a number on the scale, but making weight loss something you CAN actually achieve.

And to be fair, thinking in terms of combination therapy is nothing unusual these days. Slower-dose GLP1s paired with metformin can sometimes:

attack insulin sensitivity from more than one direction

take the edge off appetite and keep you satisfied

let smaller doses work with fewer side effects along the way

give your metabolism a broader push in the right direction

protect lean tissue better, provided protein intake is adequate and you are lifting

Also, the muscle point you raised deserves more weight than it usually gets. A person carrying a good amount of muscle can keep glucose and A1C looking fine for years, simply because muscle soaks up glucose so effectively... even while resistance builds quietly underneath. That is exactly where fasting insulin and HOMA earn their keep in a clinical setting.

Those are good questions, and you are already looking past the idea of picking whichever drug drops weight fastest, which is really the conversation that matters over the long term with a HOMA that high.


https://www.reddit.com/r/InsulinResistance/s/CEVZ5LekEG


A thread titled "6 months Metformin - weight down but HOMA up?"

View attachment 245

So that is one more argument for putting Zepbound/tirz ahead of the rest. Or possibly grey reta.

I never got a baseline fasting insulin number back then, but across a year my A1c came down from 6.1 to 5.3, and tirz on its own did most of that. Fasting insulin looks normal, even great, these days.
I would be cautious about lifting a single Reddit anecdote straight onto the person who started this thread. The two of them are not comparable: different metabolic profiles, different labs, different symptoms, different body composition, different medical histories, and different goals for treatment.

The doctor in question is basing advice on that patient's own clinical picture, and the approach does have real evidence behind it. One stranger's story from the internet is nowhere near enough to settle what will or will not help the original poster.

Tolerance varies enormously from person to person as well. Plenty of people handle metformin without a hitch; others get further with extended release, a gentler ramp-up, dose tweaks, or just letting the body adapt in its own time. And sure, for some people it never turns out to be the right drug at all.... that is a legitimate outcome too. Writing it off as certain to be miserable or pointless before a single dose, though, strikes me as giving up too early.

And a high HOMA does not automatically mean skipping everything else and going straight to tirzepatide. Medicine rarely boils down to one drug per metabolic issue.
 
Any idea why the doctor is steering toward semaglutide rather than tirzepatide? Coverage, supply, or some other factor? Tirz also tends to bring less nausea and vomiting with it.

Or maybe the OP (@Cluni0n) just used Ozempic as a stand-in example? Either way, their reta is already on the way:


/community-link/thread/15813/


Which means the sharper comparison, at least on a marker like HOMA, would be reta plus metformin against reta by itself:

Gemini said:


e708098a5f91289f89f9f786e108663384820ecdd953856997769fd40b6cfd92.webp


Click to expand...

And if the goal is the best possible outcome for her particular situation, it may be worth the OP being more upfront with her doctor about any reta she plans to run. Since reta is generally regarded as stronger than Ozempic/sema on insulin resistance, there may be less reason to stack metformin on top.
 
mybodyisasewer said:

Plenty of things here are new to me - metformin being muscle sparing on a deficit, the stomach issues or diarrhea, using it as a senolytic. jardiance is another one i had never heard of, though at first glance it looks interesting, it makes you pee out sugar? So it seems i have a bunch of rabbit holes to go down.

Personally i used metformin years ago, for blood sugar control when i was heavier and starting HGH. It worked well enough i suppose - i can only assume it kept my blood sugar normal - and i had no noticeable side effects. I do not need it now, especially while taking reta; combining the two would drop blood sugar a lot.

Going by the bro science, you should try it. Metformin is cheap, safe and, as far as i knew until now, well tolerated. It is a low risk, high reward bet.
Worth noting that metformin brings plenty of secondary perks as well. Many who ran it alongside HGH simply keep going with it afterwards. Especially anyone who has ever dealt with elevated blood pressure. The literature on it is substantial.
 
Calm Logic said:

Any idea why the doctor is steering toward semaglutide rather than tirzepatide? Coverage, supply, or some other factor? Tirz also tends to bring less nausea and vomiting with it.

Or maybe the OP (@Cluni0n) just used Ozempic as a stand-in example? Either way, their reta is already on the way:


/community-link/thread/15813/


Which means the sharper comparison, at least on a marker like HOMA, would be reta plus metformin against reta by itself:

Gemini said:


View attachment 246

Click to expand...

And if the goal is the best possible outcome for her particular situation, it may be worth the OP being more upfront with her doctor about any reta she plans to run. Since reta is generally regarded as stronger than Ozempic/sema on insulin resistance, there may be less reason to stack metformin on top.
OP here - I have 2 paths in front of me: order some grey Reta, oooor go with metformin+ozempic. I have not bought the reta yet bc I want all my lab results plus the abdominal ultrasound back first, and also bc I am waiting to see how the EU restock looks lol, so for now I am just reading as much as I can to work out what suits my case best 🙂 - I started digging into this combined approach a few days ago, which is why I posted this thread.

OG tirz is off the table, way beyond what my budget allows. Grey tirz could work in theory, though if it came to that I think reta appeals to me more.

Hope that clears things up!
 
Go with whichever path lets you bring down A1c and fasting insulin while also shedding weight.
 
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