Questioning InBody Accuracy – Looking for Objective Input

[BALLISTIC]

I took an InBody 570 scan this morning and, honestly, I’m questioning how realistic the results are and wanted some informed feedback from people who understand the limitations of BIA.

Context matters here:
I was 100% fasted no food, not even a sip of water beforehand. Scan was done first thing, no training prior. As most know, hydration status heavily influences impedance based readings, especially lean mass and BF%


On top of that, there are some recent variables: I started Retatrutide 4 weeks ago at 265 lb currently 3.5mg, and 500 cruise Test C and 6IU Opti GH.

Diet for the last month has been extremely consistent. 200g protein daily, largely via shakes and meal replacements. One solid meal nightly, typically, Fish or 94% lean ground beef, rice, shredded carrots, snap peas, sprouts, radish, green onion. This is a large meal with around an additional 50 to 75g protein given the source. Light seasoning, occasionally Bachan’s Japanese sauce for palatability. Very low variability, low sodium swings, minimal processed food.

The scan spit out numbers that look exceptionally favorable (very low BF, very high lean mass), which raises flags for me rather than ego boosts. Between fasting, zero hydration, recent GLP/triple-agonist weight loss, I’m wondering how much lean mass inflation and fat mass suppression could be occurring. I understand InBody is best used for trend data under identical conditions, not as an absolute diagnostic...but I’m curious.

How much can acute dehydration skew LBM/BF% in muscular individuals?

Has anyone seen artificially low BF readings when scanning fasted and dry?

For those running GLP-1 / GIP / GCGR agonists, did your scans normalize once weight stabilized?

Not looking to cherry pick results, just trying to interpret the data honestly and decide whether this scan is useful or essentially noise. I will conduct for ups.

Appreciate any insight from people who’ve dug into this beyond surface-level explanations.

Friend works at the gym and she obtained her pro card a while back. She overlooked it and confirmed it's relatively accurate at an EYEBALL level. Just looking for further insight.

 

[ETliens]

My gym has an InBody that I’ve used quite a bit. It’s only decent, not even great, for showing trends. I found that carb and water intake greatly affected my results. The body fat portion is TOTALLY useless. It’s always put me 6 -9% lower than my actual body fat. My most recent scan showed me at 6.5% body fat and at the time I was closer to 14%.

I should try it again now that I’m leaner. It’ll probably put me at something outrageous like 3%!

At this point I’ve given up on InBody. I purchased a three pack deca scan for Black Friday and I’ll just rely on that.

 

[BALLISTIC]

My gym has an InBody that I’ve used quite a bit. It’s only decent, not even great, for showing trends. I found that carb and water intake greatly affected my results. The body fat portion is TOTALLY useless. It’s always put me 6 -9% lower than my actual body fat. My most recent scan showed me at 6.5% body fat and at the time I was closer to 14%.

I should try it again now that I’m leaner. It’ll probably put me at something outrageous like 3%!

At this point I’ve given up on InBody. I purchased a three pack deca scan for Black Friday and I’ll just rely on that.

Yeah and that's why I question it. I have a great resource for eye on analysis. But this was a first.

I have visible spider web vascularity 24/7 throughout abdomen, shoulders, chest, legs, lats pretty much damn everywhere. But that's also been genetic my whole life. The weight was extremely accurate as I've been measuring and weighing for the last month on Reta. I haven't lost size in measurement necessarily but have lost weight as indicated by the scan. My home scale showed 1lb difference in same attire. 4lb variance nude. I have zero desire for food on Reta. I get hunger cravings, but 1 or 2 bites satisfies, anything more I tend to get hateful. My evening meal has been the easiest. But I wouldn't make it without chugging shakes.

 

[Biggerisbetternl]

Just a quick search and the study I found:

Effects of hydration and dehydration on body composition analysis: a comparative study of bioelectric impedance analysis and hydrodensitometry - PubMed

Since 1983, bioelectric impedance has been researched with respect to its validity and reliability in the determination of body composition. It continues to be compared to hydrostatic weighing, the anthropometric "gold standard". This study was designed to investigate the relationship between...

pubmed.ncbi.nlm.nih.gov

The authors noted that hydration status alters body composition estimates, with dehydration lowering apparent %BF.

Accuracy seems to be in the 3-5% margin of error for bodyfat. so Yeah.

 

[BALLISTIC]

Just a quick search and the study I found:

Effects of hydration and dehydration on body composition analysis: a comparative study of bioelectric impedance analysis and hydrodensitometry - PubMed

Since 1983, bioelectric impedance has been researched with respect to its validity and reliability in the determination of body composition. It continues to be compared to hydrostatic weighing, the anthropometric "gold standard". This study was designed to investigate the relationship between...

pubmed.ncbi.nlm.nih.gov

The authors noted that hydration status alters body composition estimates, with dehydration lowering apparent %BF.

Accuracy seems to be in the 3-5% margin of error for bodyfat. so Yeah.

Hey thanks, I haven't looked into that yet. I was merely informed by my friend to go at it the same way each time. So I decided fasted, even from fluids temporarily to keep accuracy over time consistent. I stay hydrated with the exception of sleep. Typically I consume 34oz of water immediately upon waking. My understanding is everyone wakes up dehydrated, however, I've never craved water immediately, I consume 34oz based off this theory. I generally consume 1.5 gallons daily whether training or not. Slightly more in the summer as I live in a swamp.

Thank you again I'll read up.

 

[Coachie]

So much inaccuracy in these scans. Here is my very recent post about them:

Inaccuracies of body scans - Dexa (x2), Evolt and Inbody

 

[Biggerisbetternl]

@Coachie Great post, the Dexa scans were pretty close to eachother. The other two scans were basically bs it seems.. Have you looked into MRI scans? (costly I know)... Would be interesting to see a similar setup including MRI.

 

[BALLISTIC]

Just realized the image was resized

 

[BALLISTIC]

So much inaccuracy in these scans. Here is my very recent post about them:

Inaccuracies of body scans - Dexa (x2), Evolt and Inbody

Yeah great post. That clarified it substantially. The general consensus seems right fasted from everything. But the result were still jacked up.

 

[Coachie]

Great post, the Dexa scans were pretty close to eachother. The other two scans were basically bs it seems.. Have you looked into MRI scans? (costly I know)... Would be interesting to see a similar setup including MRI.

I would love to continue to compare body scans. But the price goes up a little too much at the next level with MRI scans and Prenuvo-type scans.

 

[BALLISTIC]

@Coachie Great post, the Dexa scans were pretty close to eachother. The other two scans were basically bs it seems.. Have you looked into MRI scans? (costly I know)... Would be interesting to see a similar setup including MRI.

@Coachie what's your take in calibration? Obviously from your results that could be a huge factor. Another nuance for mine was they just calibrated it and I was the second to scan. Google searching does morning to provide info other than "not necessary unless motherboard is replaced".

 

[Biggerisbetternl]

I would love to continue to compare body scans. But the price goes up a little too much at the next level with MRI scans and Prenuvo-type scans.

What would it costs in your area?

 

[New2theGame!!]

Just realized the image was resized
View attachment 368431

Good numbers overall. BMI looks a little off compared to the 9% bf

 

[BALLISTIC]

Good numbers overall. BMI looks a little off compared to the 9% bf

I agree, I'm not touting but I'm jacked so it's misleading in that metric BMI often misleads to obesity due to muscle abundance. At my Pinnacle I was 285lbs and right around 10% overall. The detriment to that was I was always uncomfortable, range of motion sucked, you name it I hated it. The true mass monsters of the world are in a class of their own discomfort daily, but if it's career based it's a reasonable sacrifice.

But please understand I'm extremely humble. I use to compete as a tactical athlete with a tier 1 team. It test everything from strength, endurance, mental, accuracy, precision, teamwork... The weakest link truly hindered results. As time progressed the ego of ignoring injuries led to multiple hernia surgeries, both shoulders reconstructed, ankle surgery, hip displacement... Oh and disc protrusions. This was before the competition turned cross fit. No offense to anyone out there but CrossFit is G@y. My mother has been a physical therapist her entire life, she loves CrossFit, it keeps her well employed. End rant.

Thanks everyone for the insight. I appreciate your time in dropping knowledge.

 

[BALLISTIC]

So much inaccuracy in these scans. Here is my very recent post about them:

Inaccuracies of body scans - Dexa (x2), Evolt and Inbody

@Coachie What's your take on the segment portions. Given calibration variance, as well as, manufactures technology. Obviously accuracy is not great n terms of BF.

It appears looking at yours (close in stature)... It depicts numbers closely consistent across your scans. Some variation obviously, but you know you... So judging from your personal observance does it appear accurate in that regard?