Body Fat % on Index S2 Smart Scale Seems Inaccurate

However, Garmin expressly warns that the scale is not a medical device.

True, that it is not registered as a medical device where no notified body or FDA assessed it properly, but how many persons actually know what the definition of medical device is? And do they know what the claim "the scale is not a medical device" actually mean?

The question I have is, are the S2 usually used for weighing potatoes or used to monitor your weight, so that you potentially can calculate the pharmaceutical dose of a specific medicine? To me tracking weigh over time, can be seen as a diagnostic measurement, where my weight is a standard medical diagnostic parameter.

There is always a possibility of misuse the S2, and a label claiming not a medical device is usually not enough in court.

There are several medical devices classification from Class I to class III. To me it is arguably if the S2 should be at least a class I medical device connected to software. Years ago within the FDA there were some discussions around the 510(k) clearance, the same discussions were in the EU

For the ones that would like to know what the definition is of a medical device according to Medical Device Regulation (MDR) https://www.medical-device-regulation.eu/2019/07/10/mdr-article-2-definitions/

Opinion:

Any device that may give any impression related to our health, should be classified as a medical device, with the use proper risk management!

I am having an issue with my scales ability to measure my actual weight (AKA, its fundamental purpose). I have recieved a response from Garmin that is totally irrelevant for my issue but goes to show they are aware of the issues with the body metrics and are preparing a defence.

tl:dr; they dont think there is an issue, they just think you are fatter than you think you are. If you dont like that then you are free to return your scale.

Why Is My Body Composition Data Different When Compared to Other Tests or Scales?

• Index S2 uses more of the impedance data rather than relying more heavily on a BMI value. We have found that non-Garmin devices will use a variety of different methods to calculate body composition metrics making it very difficult to compare Index S2 values with those non-Garmin handheld devices.  
• Garmin encourages customers to use the recommendations in the above article in order to be able to accurately track their body metrics over time to determine if they are trending in their preferred direction. 
• We stand behind the scale’s performance. Like other products, the scale has an accuracy tolerance, but we meet or exceed standards for bodyweight scales

• The body composition metrics provided by Index S2 compare to known gold standard methods (Dexa scan, Bod Pod, etc.) favourably on average. However, individual users can certainly see a difference. We have often found, however, that taking a measurement with a gold standard method often reveals that a user’s body fat percentage turns out to be higher than they imagined. 

If you feel as though you are still unhappy with the body composition metrics from their Index S2 scale, it might be worth returning the scale to the retailer. 

If you in the UK, the Consumer Rights act of 2015 should help you. This gives you recourse with the retailers to repair, replace or refund if you can prove that there is a defect as long as its within the reasonably expected lifespan of the product 

"The body composition metrics provided by Index S2 compare to known gold standard methods (Dexa scan, Bod Pod, etc.) favourably on average"

As an old bloke who has just had a complete medical including Dexa scan the S2 shows body fat 80% higher than Dexa.

Again this comes back to the scale simply saying all old blokes are fat. My fat % cannot miraculously go down by  a large amount if I tell the scale I am 30 years younger.

I asked by 16 year old grandson to step on the scale - 173cm and 61kg (I'm 175cm 63kg). Scale shows body fat 24%

I should have pointed out that when my grandson used the scale it was set with my height and age. So basically the scale measured his weight and computed the body fat based on his weight and my age. In other words it made no attempt to actually measure body composition.

thats a simple but excellent test and confirms what we've believed - completely contrary to garmin's claims as posted by StevePerry1985 above. it is highly improbable that your grandson's body composition is the same as yours.

garmin should actually be prosecuted for this outright lie - anybody have contacts in a major market regulatory authority?

its not sufficient that they accept returns, they need to stop selling this fake device and make recompense for their behaviour.

No disrespect, but I find this hard to believe without a reliable source as if this story was true the mainstream media would have certainly picked up on it.