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How to measure body fat percentage?

Looking for advice on how to measure and track body-fat percentage.  My preference is a method that does not require calipers or special scales, but that may not be feasible.  I occasionally see posts from Aria users that say something like, "I ate a grape and Aria reports I went from 16% to 812% body fat".  So I'm not crazy about paying a lot of money for bad results when I'm perfectly capable of generating my own bad results.

 

I was going to send a PM to @Dominique as he has been tracking body fat percentage in TrendWeight but thought I would post here so others can benefit from the information.  Of course, if there is already an answer via an FAQ, please direct me to it, and thanks for any guidance!

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@Baltoscott and me are going to disappoint you: Scott is a fan of calipers (check this topic on the use of the Accumeasure caliper) and he’s also using a smart scale (from Withings); as to me, I have found the Fitbit Aria smart scale works very well for me: I always use it in the same conditions (first thing in the morning), I get very consistent results for BF% (as you can see in the graph in this other topic) and it also appears to match visual representations found on sites such as this one. I’ve also got two scales from Withings, and while BF% according to them isn’t identical to the estimate of the Aria, it’s very close (within 0.5-1.5%) and always in the same direction (Withings sees me leaner than Fitbit). I think with scales, it’s a case of YMMV. What may make it work for me is my diet (relatively stable intake of carbs, so the level of fluids in my body in the morning likely doesn’t fluctuate that much) and I’m of average height and corpulence, which means there are probably a lot of people similar to me in the database used by the algorithm. Of course, I also like the convenience of smart scales: weigh-ins (both weight and BF%) are automatically uploaded to my Fitbit accounts. For low-carbers or carb-cyclers, scales may not work well, as hydration would fluctuate a lot more (and BIA scales are very sensitive to hydration).

 

Something that works quite well as a proxy for fat loss/gains is your waist circumference at navel height. In my case, it was 85-86 cm at the beginning of the year at 67 kg and it’s about 79-80 cm now at around 60 kg. BF% (as estimated by Aria) went from 18.5 to 14.0% during that time. Since you’ve been dropping weight much faster, you should probably see noticeable changes weekly. 

Dominique | Finland

Ionic, Aria, Flyer, TrendWeight | Windows 7, OS X 10.13.5 | Motorola Moto G6 (Android 9), iPad Air (iOS 12.4.4)

Take a look at the Fitbit help site for further assistance and information.

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@DominiqueWhat is your opinion on Tanita's Full Body Composition digital scales? http://www.tanita.com/en/consumer-full-body-composition/ I've had one of their body fat digital scales since 1999 and was thinking of getting a replacement for it because the incremental weight accuracy is much better on recently manufactured digital scales. It's either the Aria 2 or a Tanita that I'm considering to get. The Aria 2 is less expensive than the a Tanita but the Tanita has a lot more metrics in terms of full body composition.

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@exhile: well, I have no personal experience with Tanita, but generally speaking I believe more (e.g. metrics) isn’t necessary better and I’m a bit skeptical about the ability of a BIA scale to assess things like visceral fat. So I’d rather have a scale that does the basics (weight + BF%) reliably than one that accumulates a long list of  metrics, but isn’t necessarily reliable.

 

Now, both Tanita and Fitbit make bold claims regarding accuracy:

 

Tanita: "...incorporates the very latest FDA cleared Dual Frequency bioelectric impedance analysis (BIA) technology, the first consumer body composition monitor in the world to do so. Dual frequency testing provides an additional level of accuracy to the body composition analysis process by providing essential data of a person’s intracellular and extracellular status, and is generally only found on professional grade models."

 

Fitbit: "As an FDA regulated medical device, Fitbit Aria 2 has been reengineered for greater accuracy...", "best-in-class accuracy", "Industry-leading accuracy".

 

Both feel compelled to mention the FDA, though it is unclear to me what practical benefits being "FDA cleared" or an "FDA regulated medical device" brings. Likewise, would "dual frequency BIA" be automatically superior to traditional BIA, and what is it exactly that gives the Aria 2 "best-in-class" accuracy?

Dominique | Finland

Ionic, Aria, Flyer, TrendWeight | Windows 7, OS X 10.13.5 | Motorola Moto G6 (Android 9), iPad Air (iOS 12.4.4)

Take a look at the Fitbit help site for further assistance and information.

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@DominiqueHere is a snapshot of the metrics that Tanita's products are supposed to provide:

 

tanita.JPG

Tanita states their products are the choice of athletes. I used to be an athlete in my younger days but I don't see why you would need all this information. Also, when it comes down to it all, it is the price that counts. I would say for the general public, the Aria 2 is the way to go since it measures like you say, "the basics" of (weight + BF%).

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Good idea to set up a separate discussion for this issue, @Daves_Not_Here.  @Dominique has already pointed to some of my posts.  I've got two Withings (now Nokia) scales, and an old Omron body fat scale.  I weigh about 160 right now, and the two Withings models seem to agree with each other, and also appear to consistent day to day (around17% using the normal as opposed to "fit" setting).  Omron reports about 12%. I weigh myself at a relatively fasted state -- in the morning, right after waking up and after going to the bathroom.  If I wait until later in the day I can "lower" the readings because I will have more fluid in my body.  The differences due to hydration can be significant, so it is important to weigh in at the same time of day to evaluate trends.

 

My calipers put me between 12 and 14%.  My waist measurements over the past 4 weeks (while I've been roughly 160 lbs) have been between 30.5" to 32".  (I think it was around 38" when I was at 200 lbs, but I don't have it written down anywhere).  

 

My takeaway is that saying I'm 12% or 14% or 17% body body fat is almost meaningless.  More important is whether whatever method I am using gives consistent results with repeated measurements.  I think all three scales, and calipers and the tape measure to that fairly well, but before I write it down for historical comparison purposes, I usually measure 3 times and take an average.  

 

 

Scott | Baltimore MD

Charge 6; Inspire 3; Luxe; iPhone 13 Pro

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@Baltoscott - I was pushing 38 to 40 waist size at my peak monstrosity, and I'm looking forward to getting back into my 32 inch clothes.  You are to be commended for getting and staying there versus my recent yo-yo.  Ah, lessons not learned will be repeated!  

 

Hearing from you and @Dominique, I'm finding my resistance to scales breaking down (I told you I have no willpower).  I am surprised you are getting 17% from your scales and 12-14% on calipers (particularly since your Omron gives you 12%).  I would think at 17% you would be lean, but at 12% have sharper muscle definition.

 

Any opinions on tape measure methods and calculators, such as https://www.active.com/fitness/calculators/bodyfat ?  I think I'm going to dig up a tape measure and start tracking the numbers just so I can measure progress while I'm shopping for the scales.

 

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@Daves_Not_Here wrote:

I occasionally see posts from Aria users that say something like, "I ate a grape and Aria reports I went from 16% to 812% body fat".


That has always puzzled me (seen a lot of that on the Aria help forum), as in the 4.5 years I’ve had my Aria, it has always been very consistent with BF%. In fact, these user comments were what prompted me to get a second scale (Withings), which turned out to behave exactly like the Aria.

 

My Aria has been exceptionally consistent during the past four weeks, with every single BF% value within a 0.5% fluctuation range (max: 14.5, min: 14.0):

 

2017-09-26_1038.png

 

 I also had a non-weight scale mini-victory this morning, as I saw 13.9% on the scale display: first time ever in 4.5 years I see a value below 14% Smiley Happy.

 

In fact, it’s because the Aria isn’t capable of rounding numbers to the nearest decimal. It actually records BF% with two decimals (which doesn’t make much sense IMO), but strips the second decimal on the display. This is what I see in the app on my phone:

 

bf_13.9.png

 

I’m excited to see if the trend will continue...

Dominique | Finland

Ionic, Aria, Flyer, TrendWeight | Windows 7, OS X 10.13.5 | Motorola Moto G6 (Android 9), iPad Air (iOS 12.4.4)

Take a look at the Fitbit help site for further assistance and information.

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Check out Estimate Body Fat ~ an ai application that uses an image to detect your body fat percentage. Just search ai body fat detector. It uses dexa scan images as a reference. Its free and easy to use. Plus it gives you information on how you can lose all the extra fat you dont need.  

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