Reta and Caffeine

Bigdog0628

Explorer
Joined
May 12, 2026
Messages
39
Reaction score
0
Location
USA
For years, my daily caffeine intake has stayed consistent. Each morning I have a few cups of coffee, and later in the day I get caffeine from another drink. But over the past few days since beginning Reta, once I have that afternoon caffeine, I end up feeling way too stimulated, and it's not a pleasant sensation. Has anyone else run into this?
 
The problem isn’t actually Reta — blame the calorie deficit. When you drink coffee with nothing in your stomach, caffeine gets taken in faster, so it can hit harder. Eating a little something beforehand, such as a banana or a light snack, slows that uptake and is gentler on the stomach.
 
Reta’s glucagon agonism ramps up sympathetic nervous system activity, and that’s the reason its heart-rate bump is larger than with the other GLP’s. So it’s believable that caffeine’s effects could be amplified too. You could either take the approach above to slow absorption, cut back on the amount, or leave out the afternoon dose. That heart-rate rise is usually short-lived, so things will likely level out as time goes on.
 
Bigdog0628 said:

For years, my daily caffeine intake has stayed consistent. Each morning I have a few cups of coffee, and later in the day I get caffeine from another drink. But over the past few days since beginning Reta, once I have that afternoon caffeine, I end up feeling way too stimulated, and it's not a pleasant sensation. Has anyone else run into this?
With reta reducing how much food you're carrying, and with the calorie deficit in play, caffeine's impact becomes stronger — and as the pounds come off, that jittery overstimulated state will in all likelihood intensify. In my own case, that's exactly what's happened. Personally, though, I don't view it as something negative. Since it's making you feel uncomfortable, the solution is to cut back on how much caffeine you take in. Try dropping a single cup of coffee, for instance, and then check how that leaves you feeling.
 
Crowreap said:

Bigdog0628 said:

For years, my daily caffeine intake has stayed consistent. Each morning I have a few cups of coffee, and later in the day I get caffeine from another drink. But over the past few days since beginning Reta, once I have that afternoon caffeine, I end up feeling way too stimulated, and it's not a pleasant sensation. Has anyone else run into this?
With reta reducing how much food you're carrying, and with the calorie deficit in play, caffeine's impact becomes stronger — and as the pounds come off, that jittery overstimulated state will in all likelihood intensify. In my own case, that's exactly what's happened. Personally, though, I don't view it as something negative. Since it's making you feel uncomfortable, the solution is to cut back on how much caffeine you take in. Try dropping a single cup of coffee, for instance, and then check how that leaves you feeling.
I'm a heavy coffee drinker too. Good to know this.
 
Coffee has been off my menu for quite a while now—my caffeine fix comes from fat burner Pills. Two weeks into Reta, I've noticed those fat burners are hitting harder, and like @lessthanhalf pointed out, Reta is probably the reason
 
PepGladiator said:

Crowreap said:

Bigdog0628 said:

For years, my daily caffeine intake has stayed consistent. Each morning I have a few cups of coffee, and later in the day I get caffeine from another drink. But over the past few days since beginning Reta, once I have that afternoon caffeine, I end up feeling way too stimulated, and it's not a pleasant sensation. Has anyone else run into this?
With reta reducing how much food you're carrying, and with the calorie deficit in play, caffeine's impact becomes stronger — and as the pounds come off, that jittery overstimulated state will in all likelihood intensify. In my own case, that's exactly what's happened. Personally, though, I don't view it as something negative. Since it's making you feel uncomfortable, the solution is to cut back on how much caffeine you take in. Try dropping a single cup of coffee, for instance, and then check how that leaves you feeling.
I'm a heavy coffee drinker too. Good to know this.
There's another thing I've found really fascinating: your calorie intake can stay identical day to day, yet caffeine's effect on you shifts according to how much food is sitting in your stomach. It comes down to the amount of food volume you took in the previous day, and identical calories don't change that. So from what I've seen, how strong caffeine feels is tied not just to calories but also heavily to food volume.
 
No jitteriness at all. I have 2 cups each morning, beginning at about 5AM. My wife follows the same routine, and neither of us has had any problems. @Bigdog0628, what dose are you taking?
 
I use Reta and consume 150-300mg of caffeine on most days. I don't get jittery—actually, I could fall asleep...
 
BNLFL said:

No jitteriness at all. I have 2 cups each morning, beginning at about 5AM. My wife follows the same routine, and neither of us has had any problems. @Bigdog0628, what dose are you taking?
I left out that my caffeine intake is 400-600 mg
 
Bigdog0628 said:

BNLFL said:

No jitteriness at all. I have 2 cups each morning, beginning at about 5AM. My wife follows the same routine, and neither of us has had any problems. @Bigdog0628, what dose are you taking?
I left out that my caffeine intake is 400-600 mg
No clue what amount that would be.
 
typical caffeine tablets contain 100mg

a normal tea serving has 50-100mg

coffee ranges around 70-150mg? coffee varies more, but the common figure sits near 100mg
 
This thread is excellent. Reta gets plenty of justified acclaim, but those who are overly enthusiastic might frighten themselves if they fail to begin with a slow, low dose and also ignore guidance such as what appears here.
 
lessthanhalf said:

typical caffeine tablets contain 100mg

a normal tea serving has 50-100mg

coffee ranges around 70-150mg? coffee varies more, but the common figure sits near 100mg
Appreciate it.
 
Bigdog0628 said:

BNLFL said:

No jitteriness at all. I have 2 cups each morning, beginning at about 5AM. My wife follows the same routine, and neither of us has had any problems. @Bigdog0628, what dose are you taking?
I left out that my caffeine intake is 400-600 mg
Wouldn't that amount be pretty high for daily intake?
 
Bigdog0628 said:

For years, my daily caffeine intake has stayed consistent. Each morning I have a few cups of coffee, and later in the day I get caffeine from another drink. But over the past few days since beginning Reta, once I have that afternoon caffeine, I end up feeling way too stimulated, and it's not a pleasant sensation. Has anyone else run into this?
With both Reta and Tirz, this is something I experience. I've had to make a point of ordering smaller Starbucks drinks when I buy them there, and of sipping less at a time. I still can't get through even the smaller cup.

The strength of the shot's effects seems to control this directly. Later in the week, once hunger starts creeping back, I'm able to drink more coffee again. But during the periods when the shots are hitting hardest, there are mornings where coffee doesn't even cross my mind.
 
Beardboost said:

The problem isn’t actually Reta — blame the calorie deficit. When you drink coffee with nothing in your stomach, caffeine gets taken in faster, so it can hit harder. Eating a little something beforehand, such as a banana or a light snack, slows that uptake and is gentler on the stomach.
That hasn’t been my experience. Coffee while fasting? Done it. Coffee on a full stomach while on Reta/tirz? Also done it. Something beyond a simple calorie deficit must be at play here.
 
Back
Top