Fasting while on GLP1s — has anyone given it a go?

Tomorrow is Friday, so I'll eat dinner early. My Reta shot for the week happens Saturday morning, and I plan to hold out until some point on Sunday.

Might add a MOT-C dose and hit the gym without eating

Compared with every other fast I've done, one thing is different this time: I've cut my caffeine way back, from 4-5 cups of black coffee daily (which is what I used to drink during fasts) to just 1 earl grey tea per day, so this round will be a pure water fast.
 
Mochizuki0124 said:

Nate2plate said:

Mochizuki0124 said:

What's strange is that for about 6 months I did weekly fasts lasting 24-48 hrs. Once I started GLPs, fasting became more difficult for me, though I do reach fullness sooner when eating — the catch is I'd need at least 2 meals per day. My guess is glucagon is involved.
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For a year I followed rolling 48s — 48 hours on, then 48 off. Looking back, I suspect my gut microbiome and other internal systems didn't benefit from that pattern. Still, certain aspects of fasting appealed to me a lot. I dropped 60 lbs that way.

Loose skin is something everyone on glp1 deals with, and fasting is an excellent route for that — atrophy will actually resolve it, no surgery required.
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I dropped roughly 20lbs during fasting. Building muscle was a real struggle, though, since my protein intake was consistently low. These days, getting enough protein is much more manageable.
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Yeah, that's the reason I'm on the glp1 train as well. When I fasted, losing muscle hit me pretty hard.
 
Mochizuki0124 said:

What's strange is that for about 6 months I did weekly fasts lasting 24-48 hrs. Once I started GLPs, fasting became more difficult for me, though I do reach fullness sooner when eating — the catch is I'd need at least 2 meals per day. My guess is glucagon is involved.
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Same thought crossed my mind. Long before I ever discovered pep world, I was already doing keto and IF — daily 20/4 fasting plus a longer water fast of 3 to 5 days at least 1x/month to reset my gut.

Right now I'm in week #2 of an off cycle from all peps because I have a procedure coming up, and honestly it's easier to get back into fasting without the GLPs in the mix. Back when I was still cycling my peps, it was such a struggle that my daily 20/4 IF was barely doable.
 
Curious, because I've practiced IF on and off for a while — my eating window runs from about noon to 7 PM. Now that I'm about to begin Reta, and I keep reading how important it is to eat enough and get plenty of protein, I'm wondering whether I ought to drop the IF. Fitting a large daily protein amount into just those 7 hours feels hard, particularly on workdays.
 
Mr. B said:

Curious, because I've practiced IF on and off for a while — my eating window runs from about noon to 7 PM. Now that I'm about to begin Reta, and I keep reading how important it is to eat enough and get plenty of protein, I'm wondering whether I ought to drop the IF. Fitting a large daily protein amount into just those 7 hours feels hard, particularly on workdays.
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Yeah, during my first week or so on Reta I logged meals with Cronometer to spot which nutrients I kept coming up short on

Could be useful in your case

From what I hear, Reta isn’t as strong as sema or tirz when it comes to suppressing hunger or the ability to eat. That said, the slowed stomach emptying definitely makes huge meals sit heavy and feel unpleasant
 
Clavicular's Hammer said:

Mr. B said:

Curious, because I've practiced IF on and off for a while — my eating window runs from about noon to 7 PM. Now that I'm about to begin Reta, and I keep reading how important it is to eat enough and get plenty of protein, I'm wondering whether I ought to drop the IF. Fitting a large daily protein amount into just those 7 hours feels hard, particularly on workdays.
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Yeah, during my first week or so on Reta I logged meals with Cronometer to spot which nutrients I kept coming up short on

Could be useful in your case

From what I hear, Reta isn’t as strong as sema or tirz when it comes to suppressing hunger or the ability to eat. That said, the slowed stomach emptying definitely makes huge meals sit heavy and feel unpleasant
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Yeah, I've got a food tracker I plan to use. I had used it during a stretch when I was microdosing Sema a few months ago. Back then, the microdosing didn't suppress my appetite all that strongly, particularly once several days had passed before the next dose. So I was doing IF, and IF felt great for me, though I did notice it became tough to hit the protein target. I figure I'll need to work in more shakes and similar things during the Reta journey. I began today, taking it slow at 0.5, and I'll see how it goes — maybe adding another 0.5 on Tuesday.
 
Breakfast has never really appealed to me, so for most of my life I've kept a daily fasting window of 16-18 hours. Before I began tirz, I would also throw in 24-36 hour fasts 1-3 times each week. After starting tirz, though, every attempt at a full 24 hour fast has fallen short, and I've made several tries. Getting enough calories each day is already a challenge for me, so maybe that's actually a good thing.
 
Tirzepatide has made fasting feel effortless for me, though I've only done the OMAD style. Prior to starting Tirz, I could go without eating from my noon meal until lunch at 1:00 PM.
 
FartfulCodger said:

Tirzepatide has made fasting feel effortless for me, though I've only done the OMAD style. Prior to starting Tirz, I could go without eating from my noon meal until lunch at 1:00 PM.
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When you sit down to eat, how large is that meal? Does it leave you feeling like the boy in Charlie and the Chocolate Factory who swells into a giant ball?

On Reta, if I put away a big amount of food, my system immediately signals that it isn’t pushing contents out of the stomach very quickly.
 
Clavicular's Hammer said:

FartfulCodger said:

Tirzepatide has made fasting feel effortless for me, though I've only done the OMAD style. Prior to starting Tirz, I could go without eating from my noon meal until lunch at 1:00 PM.
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When you sit down to eat, how large is that meal? Does it leave you feeling like the boy in Charlie and the Chocolate Factory who swells into a giant ball?

On Reta, if I put away a big amount of food, my system immediately signals that it isn’t pushing contents out of the stomach very quickly.
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As I increase my Reta dose, I figure I'll need to keep an eye on how my stomach reacts to what I eat.
 
Clavicular's Hammer said:

FartfulCodger said:

Tirzepatide has made fasting feel effortless for me, though I've only done the OMAD style. Prior to starting Tirz, I could go without eating from my noon meal until lunch at 1:00 PM.
Click to expand...
When you sit down to eat, how large is that meal? Does it leave you feeling like the boy in Charlie and the Chocolate Factory who swells into a giant ball?

On Reta, if I put away a big amount of food, my system immediately signals that it isn’t pushing contents out of the stomach very quickly.
Click to expand...
While using Tirz, my routine was to skip food all day and only have an evening meal. Even so, once I started eating, only about 1/3 to 1/2 of what I’d usually have at dinner was enough to make me feel full. After that, dessert held no appeal at all — something that never used to happen with me. And yes, there were definitely moments when I felt bloated.
 
35hr fast complete

Got up and had mot-c

Took the dog out for a 1.5 hr walk

Did a 1.5 hr light light light gym session including deep stretching

19 minute sauna

Then went to a icy mountain river with friends and did a few dips

Really shocking the system acting ampk in every imaginable way

Then bed. Woke up, did more mot-c, took glycine, NAC, psyllium husk, and electrolytes and went for a 5km jog with the dogs, lots of walking.

Feeling great, hope my body got something good out of it.

Really hoping to make this a monthly thing.
 
For me, the day following my reta injection tends to work well as a fasting day. It's not something I do weekly, but when I choose to, it's not hard. My routine is usually a light lunch early in the day, then I fast for 24 hours until an early lunch the next day. On reta, it's honestly pretty simple, and it's a helpful adjustment to raise or lower my weekly calorie intake based on how things are progressing.
 
Just wrapped up a 112-hour water fast ahead of a procedure 🎉 not my longest stretch, though.

Broke the fast with bone broth first, then 1 hr afterward had baked avocados done "sushi" style, and by the 2nd hr I ate half of a 3x3 Flying Dutchman from INO. Planning to re-pin my reta on Wed, starting back at a low dose.
 
HRH_IceQueen said:

Just wrapped up a 112-hour water fast ahead of a procedure 🎉 not my longest stretch, though.

Broke the fast with bone broth first, then 1 hr afterward had baked avocados done "sushi" style, and by the 2nd hr I ate half of a 3x3 Flying Dutchman from INO. Planning to re-pin my reta on Wed, starting back at a low dose.
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Nice!

Did you fast at all before starting Reta or other GLP1s?
 
Clavicular's Hammer said:

HRH_IceQueen said:

Just wrapped up a 112-hour water fast ahead of a procedure 🎉 not my longest stretch, though.

Broke the fast with bone broth first, then 1 hr afterward had baked avocados done "sushi" style, and by the 2nd hr I ate half of a 3x3 Flying Dutchman from INO. Planning to re-pin my reta on Wed, starting back at a low dose.
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Nice!

Did you fast at all before starting Reta or other GLP1s?
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Thanks, and yeah — prior to finding Reta and other peps, I followed keto plus IF. Once a month I typically go for extended fasts of roughly 3 to 5 days. Over about 2+ yrs of keto and IF I lost around 30 lbs, then Reta helped me shed another 20 in roughly 6 months, so I'm definitely staying on Reta since I've still got a few more to lose.
 
I came across something saying that fasting may be risky when you're on GLP-1, since it might cause issues with the gallbladder. Does anyone have any info on this?
 
Ajejebrazorf said:

I came across something saying that fasting may be risky when you're on GLP-1, since it might cause issues with the gallbladder. Does anyone have any info on this?
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Perhaps increase your fluid intake quite a bit? Whether we fast or not, our bodies keep producing waste.
 
lastresort said:

Ajejebrazorf said:

I came across something saying that fasting may be risky when you're on GLP-1, since it might cause issues with the gallbladder. Does anyone have any info on this?
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Perhaps increase your fluid intake quite a bit? Whether we fast or not, our bodies keep producing waste.
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What makes the risk go up

    • Bile Stasis: When you take GLP-1 drugs and go without meals, the gallbladder empties less frequently, so bile stays put for longer than it should.
    • Rapid Weight Loss: Losing weight quickly pushes more cholesterol into the bile, which can lead to stones or sludge.
    • Extended Fasting: Going a long stretch without eating means no fat from food reaches the gut to set off the usual gallbladder emptying.
 
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