Guide
How accurate are body fat scales designed for home use?
by Oliver Fischer
Withings "Body Scan": a body fat scale that can do much more
7/1/2026
Translation: machine translated
Pictures: Stephan Lamprecht
With the smart "Body Scan" scale from Withings, you can not only monitor your weight. It can also record an ECG on request and keep an eye on your heart health. And it does this really well.
I go running regularly for basic fitness. Not a marathon or anything like that. I'm really not a sports freak. Just a few kilometres through parks, along the Elbe in Hamburg or the Spree in Berlin. To track my physical condition, I'm testing the «Body Scan» scale from Withings, which the manufacturer provided me with.
As the name suggests, the scale can do more than just weigh you. According to the manufacturer, it can also:
- evaluate body composition (body fat percentage, muscle mass, visceral fat)
- record an ECG
- output heart rate
- determine pulse wave velocity
- determine the vascular age
- evaluate my nerve health
I'm really excited about this
Chic, but not easy to care for
When unpacking, the scales are surprisingly heavy at almost five kilograms. My test model is black, the high-gloss surface is made of glass. The thing feels solid and valuable.
I think I'll have to clean the «Body Scan» frequently to keep it looking as good as it does. You can see every speck of dust, every drop of water and every fingerprint on the surface.
Nothing works without an app for now
The printed quick guide explains the first steps. Very important: I need the Withings app for my smartphone. I can only set up the scale once I have created a user account. So just getting on the scale is out of the question for now.
Downloading and opening an account is quick and easy. I have to go to «Devices» in the app and tap the plus sign. Only then do I switch on the scale.
A setup wizard helps me and guides me through pairing via Bluetooth. The app then asks for my Wi-Fi access data. If everything fits, it takes a few seconds and I'm ready to go.
The first weighing is a test of patience
After setting up, the app offers me the opportunity to familiarise myself with the functions. There is a short introduction to each health function. Withings probably expects me to read it carefully. But I finally want to measure! So I impatiently tap everywhere on «Activate».
And so it finally starts. A rod connected via a cable is attached above the coloured screen of the scales. I pull it out and make sure that each of my hands is holding one of the two electrodes as I step onto the scales with bare feet. The health functions don't work in socks.
A complete measurement cycle starts with the weight. Because the «Body Scan» reacts to the slightest movement of the feet, it takes a moment for my weight to appear on the display. And I have to be honest: this scale is just as unfriendly as all the other scales. I am far too heavy. Cough. But that could also be due to my love of pizza. Ok, on with the text ...
If older measurement results are already available, the scales show me the difference and thus a tendency as to whether the weight is going up or down. (I have to cry.) The final step is a brief calculation of body composition. I get the percentage of muscle and fat mass in per cent. (I have to cry even more.)
Important in this context: Compared to a medical examination, devices for home use only show an approximation. They show trends and help me to categorise my readings. My colleague Oliver has explained exactly why this is difficult
EKG and the health of the nerves
Once the weighing is complete, it's time for the ECG. According to the instructions, I should remain as still as possible. The «Body Scan» now records a 6-lead ECG for 30 seconds. More on this later. If the device detects no abnormalities, «Sinus rhythm» lights up in green. The scale also shows me the measured pulse rate.
How accurate is the ECG that the «Body Scan» writes? The scale has CE approval as a medical product. However, this does not mean that the results are as accurate as those from a doctor.
This should be obvious to anyone who has ever been to a doctor's surgery for an ECG. You are wired up with lots of electrodes. With the scale, you only have the measuring rod in your hand. So this ECG can't be as accurate as the professional one. Recognising a mild heart attack or other cardiac insufficiency is not always entirely clear, even for doctors with a professional ECG
However, the «Body Scan» can detect atrial fibrillation, a cardiac arrhythmia that increases the risk of stroke. The Withings software also evaluates arterial stiffness (PWV). This elasticity of the arteries is an indicator of cardiovascular risk and high blood pressure.
But: If you feel you have suffered a heart attack or are at risk of one, you don't belong on the scales, but in the emergency room!
Next stop: the health of your nerves
After writing the ECG, I'm still not finished. I've been on the scales for a total of 70 seconds. Now the «Body Scan» determines my «nerve health». You have no idea what that is? Me neither so far. That's why I'm making myself smart.
The Nerve Health Score (NHS) from Withings analyses how my nervous system controls the activity of the sweat glands on my feet. A weak electric current runs through my feet. The software uses this to recognise whether there is any damage to the peripheral nerves. Because such «peripheral neuropathy» can be an indication of diabetes.
The scale displays the value in a number between 0 and 100 as well as a qualitative assessment between «normal» and «low».
Finally, the screen also shows the current weather and an assessment of the air quality at my location. Now that's what I call all-round service.
The «Body Scan» can distinguish between up to eight people
The scale is suitable for shared flats and families, as it can distinguish between up to eight people. As the owner of a main account, I can create sub-accounts in the app. The people I enter there receive an invitation to register their own account. Withings explains the exact process in detail online.
Since the «Body Scan» can't recognise me directly, it shows the name of the person it thinks is on the scale on the display. How does it differentiate between people? By their weight. If you stand on the scales, it won't even offer the name of your child if they are 20 kilos lighter than you.
However, if you use the scales with several people who are close in weight, you will have to choose between the names for each measurement. Don't worry: if this goes wrong, the measurements can also be assigned to another person in the app.
Individualise measurements
Measurements whose results I am not interested in can be deactivated in the app. They are then skipped and no longer appear in the dialogues on the scale. However, I cannot change the display order.
In the app options, I also have the choice between different modes:
- Eyes closed: This does not mean that I should stand on the scales with my eyes closed. The display does not show any values in this mode. They only end up in the app. This is intended for people who prefer not to know their weight and vital signs so precisely.
- Weight only: This mode is important for all people who wear a pacemaker. If I activate this mode, the «Body Scan» is simply a scale. The health functions, including the determination of body composition, are deactivated. In this mode, no current is passed through the body, which could literally throw a pacemaker out of step.
- Athlete mode: Okay, I will probably never activate this mode. But if you exercise more than eight hours a week and have a resting heart rate below 60 beats per minute, Withings recommends Athlete Mode.
- Pregnancy mode: Of course, pregnant women gain weight with a baby on board. In this mode, the scale not only determines the weight, but also shows the weight gain per week and puts this in relation to people of a similar weight.
I don't need Withings+
In the app, Withings advertises the Withings+ plan a lot. It gives me tips for workouts and nutrition, all based on my various measurement data. However, I can also use the «Body Scan» without this plan and still have access to all my values. As soon as a new device is registered for a user account with Withings, the service is free for four weeks. Just advertising.
The numerous results and analyses in the app are enough for me. And since I can't get the scales to show a positive result, I'm going for a run now.
In a nutshell
Luxury for the health-conscious
The "Body Scan" looks classy and stylish and has its price. It would be too expensive for a simple body scale. However, anyone who enjoys tracking their values will get their money's worth with the scales, although the measured values can of course not keep up with a medical examination. I like the fact that it is easy to set up several accounts and assign different modes.
Pro
- Functional diversity
- Simple set-up and operation
- Individual profiles for up to eight people
Contra
- susceptible to dust and marks
Header image: Stephan Lamprecht
Hamburg local, bookworm, and ice hockey fan. Dad and granddad. Constantly tinkering around with my smart home setup. I love DIY, the outdoors, fashion, and cosmetics.
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