I'm almost 9 weeks post-op and trying to figure out if I'm on track. I started my 2 week diet at 239 and was 223 the day before surgery. Since surgery, I am down to 204. (So much slower since surgery!)

Here's where it gets tricky. If my goal weight is 155 lbs and I use my starting weight from the day I began my 2 week diet, I had an 84lb weight loss goal and am currently at around 41% of excess weight lost. But if I use my day of surgery weight, I had a 68lb goal and am at only 28% lost. This feels like a big difference.

I've seen some sources say count your weight loss during the immediate pre-op diet, and others say no, don't count it. Are there any actual rules, or is everyone just making this stuff up as they go?

20 minutes ago, NickelChip said:

For me, it provides peace of mind to see numbers (totally get that not everyone feels that way).

nah, i get it, i'm a numbers gal myself, and i LIVE for tracking and data and spreadsheets!

20 minutes ago, NickelChip said:

So I was hoping for a more definitive answer on how doctors calculate this type of thing.

ok,so if i were to respond to this specific statement then, my surgeon made his calculations with my weight when i first got accepted into the program...which was 2+ YEARS BEFORE my actual surgery (long story, but i backed out twice before i finally went through it).

granted, for ME, it didn't really make a difference because i was the same weight on my acceptance date in 2016, as i was 2 weeks prior to my surgery date in 2018. but im sure many others could not say the same if they were to use the same barometer.

long story short, "excess weight" is arbitrary, and the calculations are different depending on who you ask.

your best measure of success and progress in the endeavour of weight loss is yourself. is your weight loss graph trending down? yes? then YAY! again, you are doing great...but you don't need me (or anyone else) to validate that, you can see it yourself in your numbers and hard work ❤️ .

Edited April 24, 20242 yr by ms.sss

I think a lot of us fall into numbers - we are bound to at least at some point.

Unfortunately I don't ever think there is a doctor/scientific answer to really calculate it. It's almost the same as why we all have so many different programs - not only our bodies are different, but every doctor has a different take in their "expert opinion".

I just had my 1 year post-op visit on Monday, and my surgeon definitely counts my weight loss total from the date I had my consult visit January 2023. I have always kept 2 running totals from before my pre-op diet to the day of surgery weight. Personally I feel like all pounds count and it's an accomplishment to see those numbers go down both before and after the surgery.

19 hours ago, Spinoza said:

Calculates me at 182 at 18 months. Which I would have been thrilled with. Even more thrilled to get lower but honestly I had not *that* much of a say in it. My body kind of decided. ?

At my highest weight its tell me 188lbs at 18m but my pre-op weight its tell me its 179lbs. However in both scenarios I am weighing less than the 6months weight and I am 14weeks post op. So hey I call it a win!

21 hours ago, AmberFL said:

At my highest weight its tell me 188lbs at 18m but my pre-op weight its tell me its 179lbs. However in both scenarios I am weighing less than the 6months weight and I am 14weeks post op. So hey I call it a win!

Using my day of surgery weight, the calculator suggests I'll be 195lbs at 3 months. I'm 204.4 today, but assuming this blasted week-long stall breaks soon, it seems likely I'll be somewhere around there in another 26 days. It tells me to expect 178lbs at 3 months and 158lbs at a year, with a low of 151lbs at 18 months. I would be pleased as punch with that if it happens! That would be exactly 100lbs down from my highest weight, which seems unreal.

49 minutes ago, NickelChip said:

Using my day of surgery weight, the calculator suggests I'll be 195lbs at 3 months. I'm 204.4 today, but assuming this blasted week-long stall breaks soon, it seems likely I'll be somewhere around there in another 26 days. It tells me to expect 178lbs at 3 months and 158lbs at a year, with a low of 151lbs at 18 months. I would be pleased as punch with that if it happens! That would be exactly 100lbs down from my highest weight, which seems unreal.

totally doable!! You got this!!

I find the calculator on the Mexico site to be rather inaccurate for me, but everyone varies. Age and surgery type, as well as co-morbidities all impact weight loss rate. It thinks I should be at 212lbs at 6 months but I'm at 240 with 6 days to go. Not gonna happen. It also thinks I should be at 170 by 12 months, but that's not very likely either.

I've always used the following one as it takes into account the different surgeries and looks just like the one my surgeon uses. They calculate from the highest weight, it is important to include that because if you have a lot of weight loss before surgery your percentages may track differently and your post op weight loss may be slower. I've seen this happen to several people with surgeons calculating it improperly, or applying the bypass trajectory to a DS patient, which is a disaster and very stressful for the patient! This one takes into account much more like your age, ethnicity, and pre-existing conditions:

https://riskcalculator.facs.org/bariatric/?_ga=2.112690692.1282950073.1698781773-393992475.1698781773

According to this one I should be at 78 lbs down for my DS surgery at 6 months. I'm at 80 lbs down. My weight loss has tracked along with this thing pretty steadily, give or take 15 lbs, since surgery, except for my 6 week stall. It puts me at 202 by 12 months out, but DS patients lose for 18-24 months post op, so I should be at 170 sometime in that 12-24 month period!

In the end these are all just estimation tools. Our bodies do what they will and we make the most of it. Still, it is nice to have a loose guideline to follow.

Edited April 26, 20242 yr by ChunkCat

All those calculators are just averages so try not to get too caught up in what they say you’ll have lost at certain times. Some will lose more. Some will less. Some will lose as they say. That’s how averages work. And it may change time frame to time frame. Treat it only as an idea of what might happen not what will happen. You may end feeling like you’re failing if you look at their results as gospel.

10 hours ago, ChunkCat said:

I find the calculator on the Mexico site to be rather inaccurate for me, but everyone varies. Age and surgery type, as well as co-morbidities all impact weight loss rate. It thinks I should be at 212lbs at 6 months but I'm at 240 with 6 days to go. Not gonna happen. It also thinks I should be at 170 by 12 months, but that's not very likely either.

I've always used the following one as it takes into account the different surgeries and looks just like the one my surgeon uses. They calculate from the highest weight, it is important to include that because if you have a lot of weight loss before surgery your percentages may track differently and your post op weight loss may be slower. I've seen this happen to several people with surgeons calculating it improperly, or applying the bypass trajectory to a DS patient, which is a disaster and very stressful for the patient! This one takes into account much more like your age, ethnicity, and pre-existing conditions:

https://riskcalculator.facs.org/bariatric/?_ga=2.112690692.1282950073.1698781773-393992475.1698781773

According to this one I should be at 78 lbs down for my DS surgery at 6 months. I'm at 80 lbs down. My weight loss has tracked along with this thing pretty steadily, give or take 15 lbs, since surgery, except for my 6 week stall. It puts me at 202 by 12 months out, but DS patients lose for 18-24 months post op, so I should be at 170 sometime in that 12-24 month period!

In the end these are all just estimation tools. Our bodies do what they will and we make the most of it. Still, it is nice to have a loose guideline to follow.

This one took a little more math since they give you pounds lost instead of what weight you will be, but I liked that I could see it month my month. The funny thing is the risk calculator one is more aggressive/optimistic in terms of my weight loss. The Mexico one says I'll be 195 at 3 months but the Risk one says 5lbs lower. Oh well, as everyone says, this is just an average, no matter which calculator you look at. But I do find it helpful to have an idea of what to expect. It keeps me realistic.

I think it counts. When I list my high weight, for example, it is my highest weight ever before WLS. That is different than pre-surgery weight, which was my weight on the day of the surgery.

Congrats for your success and wishing you continued success.

My program too counts the highest or starting weight from the beginning. I had bypass 11 days ago and they weighed me at check in. I weighed 211. My Surgeon came to see me and she said wow you lost over 30lbs Sara be proud of yourself. I was confused and said no I only lost 10lbs and that was the pre-op??? Well I “forgot” that last August when I started this program I weighed 245. slowly over the last 8 months I did lose that 30lbs 15 right away with nutrition classes and then a few here and there, but had been stuck at 221-223 for months!! Then I lost 10lbs on the pre-op diet.
So she made me feel wonderful and I went into surgery that day feeling like a rockstar and it was great!
So I am counting my total weight loss because I worked hard for that 30lbs!!!

I am counting from my highest ever weight on my tracker on this site (352), but my surgery team and primary care doctor count from my pre-op start weight (321). There's a 2 year and 30lb gap for me, but I'm counting that for me since it was work to break old habits during that period, which helped me set the pace to be more successful post surgery.

As far as sticking to a plan, as others have mentioned, they do use average numbers. Everyone will fluctuate a little above or below at each stage. Also the weight loss progression will look more like stairs/steps rather than a straight line. You can expect a period of weight loss, followed by multiple plateaus. That's just your body freaking out over an unusual weight loss event, and recalibrating things to make sure you're not starving to death. Since it can't know you're doing it intentionally, it will retain fat and fluids as it panics, then release them once it realizes you are safe. Just stay the course, and don't get caught up on seeing a steady loss, otherwise you'll end up worrying over nothing (like I tend to do haha).

On 4/25/2024 at 9:35 PM, ChunkCat said:

I find the calculator on the Mexico site to be rather inaccurate for me, but everyone varies. Age and surgery type, as well as co-morbidities all impact weight loss rate. It thinks I should be at 212lbs at 6 months but I'm at 240 with 6 days to go. Not gonna happen. It also thinks I should be at 170 by 12 months, but that's not very likely either.

I've always used the following one as it takes into account the different surgeries and looks just like the one my surgeon uses. They calculate from the highest weight, it is important to include that because if you have a lot of weight loss before surgery your percentages may track differently and your post op weight loss may be slower. I've seen this happen to several people with surgeons calculating it improperly, or applying the bypass trajectory to a DS patient, which is a disaster and very stressful for the patient! This one takes into account much more like your age, ethnicity, and pre-existing conditions:

https://riskcalculator.facs.org/bariatric/?_ga=2.112690692.1282950073.1698781773-393992475.1698781773

According to this one I should be at 78 lbs down for my DS surgery at 6 months. I'm at 80 lbs down. My weight loss has tracked along with this thing pretty steadily, give or take 15 lbs, since surgery, except for my 6 week stall. It puts me at 202 by 12 months out, but DS patients lose for 18-24 months post op, so I should be at 170 sometime in that 12-24 month period!

In the end these are all just estimation tools. Our bodies do what they will and we make the most of it. Still, it is nice to have a loose guideline to follow.

Wow, this calculator was wayyyy more accurate to my progress than the Mexico Clinic one. At a year I was down right at 90# and this calculator estimated 100# so I'm pleased to be somewhat close ?

Thought I'd update this post because I just had the chance to attend a live Q&A session with Dr. Matthew Weiner. I talked to him about my weight loss so far and concerns about how slow my progress has felt post-op. He asked me about pre-op weight loss and what my highest weight had been, and explained that even though I was 223 going into surgery, I had started at 251 and lost 12 lbs from nutrition changes over 6 months, plus 16 lbs from the pre-op diet, so that all factors into the final weight loss expectations. He suggested in terms of what my final weight loss from the surgery might be that using the 251 starting weight could be more accurate, and that the pre-op diet weight loss would definitely help explain the slower weight loss post-op.

Bottom line, I feel so much relief hearing this explanation from him and really appreciated him taking the time to ask so many questions to get to the answer! My surgeon really hasn't given me an estimate of what I should expect to lose, although I plan to ask at my 3-month appointment next week so I can compare.

Stumbled on an Australian bariatric surgeon who recommended multiplying your starting weight by 0.7 to find the weight you may end up at. Again based on averages & they said their patients’ stats & not depended upon your surgery. Easy way to check versus searching for the online calculators if you’re interested.