Rapid weight loss question

[John316]

About 20 years ago I was at least 45 pounds overweight. I decided to do something about it. I went on a diet.

I found for me that the way to lose weight that worked the best was fasting by skipping meals. I would then have a lower calorie meal when I did eat.

My doctor, even though he told me to lose weight, asked me if I was dieting? By fasting I was dropping the pounds very quickly. My doctor did not know i was fasting and thought it might be disease that was causing rapid weight loss. I dropped those 45 pounds in about 8 months. My waist was about 6 to 8 inches slimmer and I was feeling great. My doctor warned me that fasting as I was is not a healthy way to lose that much weight.

Now that I have been using ZEPBOUND for a year I have lost over 50 pounds. I lost this weight by fasting. I am not hungry and feel fuller longer when I do eat.

I don’t hear any medical professionals advising against losing weight in this way.

Why do you think that is?

I think the answer is that being obese as I was prior to using ZEPBOUND is far more dangerous than dropping the pounds like this.

Is there more to it than this?

 

[MsGizmo]

While I don't really have anything to say about fasting per se .. losing 45 pounds in 8 months isn't even rapid weight loss. That is a healthy level of losing weight. If your doctor at the time said that it wasn't then they were wrong.

 

[BooneDonk]

I hope you have a different doctor now.

 

[mraajr]

Fasting is certainly not an unhealthy way to lose weight as long as it is not an unreasonable amount of time. The only downside really to losing weight so fast is that a fair percentage of it can be muscle. Exercise and proper protein intake can mitigate most of that.

I am not a doctor, but I believe that the "cons" (if you even want to call them that) of GLP-1s are far outweighed by the cons of being significantly overweight. It is not even a question in my book. Obesity is the cause of countless life-threatening diseases. GLP-1s up to this point have not been shown to be the cause of a single one. Any doctor that says 45 lbs. in 8 months is too much is not a doctor I would be seeing again.

 

[mercuryleaf7]

About 20 years ago I was at least 45 pounds overweight. I decided to do something about it. I went on a diet.

I found for me that the way to lose weight that worked the best was fasting by skipping meals. I would then have a lower calorie meal when I did eat.

My doctor, even though he told me to lose weight, asked me if I was dieting? By fasting I was dropping the pounds very quickly. My doctor did not know i was fasting and thought it might be disease that was causing rapid weight loss. I dropped those 45 pounds in about 8 months. My waist was about 6 to 8 inches slimmer and I was feeling great. My doctor warned me that fasting as I was is not a healthy way to lose that much weight.

Now that I have been using ZEPBOUND for a year I have lost over 50 pounds. I lost this weight by fasting. I am not hungry and feel fuller longer when I do eat.

I don’t hear any medical professionals advising against losing weight in this way.

Why do you think that is?

I think the answer is that being obese as I was prior to using ZEPBOUND is far more dangerous than dropping the pounds like this.

Is there more to it than this?

I've been taking my Mounjaro/Tirzepatide thing pretty extremely I probably not need to slow down but I get irritated with how long its going to take.

Start: 14/07/25 @ 23st
Current: 17/10/25 @19st 8lbs
Difference: 3st 6lbs
Current dose: 5mg

I'm the same as you I generally don't eat until the afternoon probably 2PM to 4PM for my first meal and then I'll be full for hours and then I'll have my second meal.
What I'm eating is usually healthy stuff all veg chicken and rice mostly.

I have heard that your liver is what processes your weightloss and you can end up with liver damage or gallstones so I probably need to think about this but without adding more junk back into my diet I find it hard to hit more calories.

 

[HumanusExMachina]

I think this paper on NIH is a pretty good summary of the effects of fasting:

The Effect of Fasting on Human Metabolism and Psychological Health

The TL;DR is that the overall effect of fasting -- especially intermittent fasting -- is positive.

 

[GLP1Pharmacist]

I don't like fasting and have concerns about low blood sugar and other impacts. Small healthy food choices spread out throughout the day is imho best.

Weight loss 0.5 - 2 lbs week is reasonable.

 

[MsGizmo]

I've been taking my Mounjaro/Tirzepatide thing pretty extremely I probably not need to slow down but I get irritated with how long its going to take.

Start: 14/07/25 @ 23st
Current: 17/10/25 @19st 8lbs
Difference: 3st 6lbs
Current dose: 5mg

I'm the same as you I generally don't eat until the afternoon probably 2PM to 4PM for my first meal and then I'll be full for hours and then I'll have my second meal.
What I'm eating is usually healthy stuff all veg chicken and rice mostly.

I have heard that your liver is what processes your weightloss and you can end up with liver damage or gallstones so I probably need to think about this but without adding more junk back into my diet I find it hard to hit more calories.

Oh, I hear that. I still have to lose more than 100 pounds at this point. Part of me wants to up my doses faster hoping to lose the weight faster but the more logical part is holding me in check because its healthier to stay at a rate of losing 2 pounds per week. So best case scenario is about 75 weeks before I get to a healthy weight according to the BMI charts.

Sigh.

 

[mercuryleaf7]

Oh, I hear that. I still have to lose more than 100 pounds at this point. Part of me wants to up my doses faster hoping to lose the weight faster but the more logical part is holding me in check because its healthier to stay at a rate of losing 2 pounds per week. So best case scenario is about 75 weeks before I get to a healthy weight according to the BMI charts.

Sigh.

I was hoping to by skinny by June next year 😂😭

 

[John316]

Thank you all! I haven’t seen that doctor in years. My doctor now is very happy with my weight loss and is encouraging me to continue.

My thought all along was that being that overweight was killing me and I needed to do something about it.

I am encouraged by everyone here. Thank you.

 

[pavlovs]

I think that small frequent meals tend to be what nutritionists think is the healthiest way to eat. One of the problems with fasting, other than the spikes and potential lows, is that while you are on the GLP1 fasting is easy. It worked for you before, but as you said, you gained it back, so it seems that fasting isn't the best way to lose and maintain the loss. The best way, while on a GLP1, is to make the healthy choices and develop the patterns that you will be able to follow for the rest of your life. As we age, it becomes harder and harder to fast. As we age, our bodies need frequent fuelings to maintain homeostasis. We cannot eat as much at one sitting, our digestion changes, and frankly. most of our meds say "take with food". I'm only 54, but I take meds four times a day, and all of them are take with food - some are even "take with a full meal".

I'm no nutritionist and not a doctor, so all of that was just my opinion🙂 Food for thought, so to speak.

By the way, you have the best user name on the forum🙂

 

[randompersonrandom]

as soon as people start trying to tell me all about how great fasting is (not here, in a conversation that's about fasting, I mean like at the office or in random places), I stop listening immediately. Bro, I'm fat because I eat too much food too often. If I could just go "hey, you know what, I'm gonna not eat food as often," I wouldn't be fat.

"Hey, I saw you mention that you're on fire. You know what works really well for me when it comes to being on fire? I've gotten into NOT burning, and it's so effective when it comes to not being on fire."