Withings Body Scan smart scales

Thu, 29 Jun 2023 00:00:00 +0000

In 2009, we bought our first Withings smart scales. Although I tried them out at the time, I soon stopped using them because of their limited functionality. Now, more than ten years later, I believe that smart scales technology has finally advanced to the point where it is genuinely useful. What’s more, I now fit the target demographic for this device: I’m a middle-aged, overweight man with a family history of heart disease who does some sport, but probably not enough. To sum up in advance: I intend to use the Body Scan scales every single day from now on. Aside from some more useful and some less useful features, it reminds me that, once you reach a certain age, you need to actively maintain your cardiovascular health. Withings has recently launched three smart scales at different price points: the Body Scan, Body Comp and Body Smart. We received the top-of-the-range Body Scan model for review. It arrived four days before we set off on our summer holiday, which is why I haven’t tested all its features. Some features require a certain minimum number of repeated measurements, so this article may be updated once I’ve used the scales for a longer period. What can the scales do? Apparently, they can measure your weight and the composition of different parts of your body (body fat and muscle percentage). They also claim to be able to distinguish between visceral and subcutaneous fat. Not all fat is equally bad: visceral fat is much more dangerous than subcutaneous fat, which can even be beneficial. If the scales could reliably distinguish between visceral and subcutaneous fat in the body, it would be an astonishing technical breakthrough (more on this later). ECG FEATURE The Body Scan scales can perform an ECG (electrocardiogram), meaning they can measure the heart’s electrical activity. An ECG can be used to detect a wide range of heart problems, but the number of electrodes (measurement points) on the body is crucial for this measurement. The medical standard is 12 electrodes. For practical reasons, devices intended for consumers are less sophisticated, and therefore have only limited ability to detect different types of heart problems. The Body Scan device has 6 electrodes, which is the best currently available in a device intended for consumers. However, such a 6-lead ECG is significantly inferior to the standard medical ECG and may even fail to detect an acute, recent heart attack. In fact, the only medical conditions that this ECG can reliably detect are atrial fibrillation and atrial flutter. Atrial fibrillation is a heart rhythm disorder that can be detected by feeling the pulse (e.g. the heart beats twice instead of once). Atrial flutter is a somewhat similar condition, characterised by a rapid heart rate (> 250/min), which may occur episodically (lasting from hours to days) but can also be continuous. Both conditions require medical treatment, and it therefore seems sensible that a consumer device should be able to detect them. However, clinical studies show that the results of mass screening for atrial fibrillation are not clearly beneficial. Experts are, in fact, divided on whether mass screening is a good idea: the 2020 guidelines issued by the European Society of Cardiology recommend mass screening, whilst the US Preventive Services Task Force and the UK National Screening Committee do not currently recommend them. Although atrial fibrillation is fairly common, it is usually secondary to other heart conditions, and the target group for the Withings Body Scan (health-conscious, middle-aged, middle-class) may not be the group that would benefit most from this feature. In one study investigating atrial fibrillation (the so-called LOOP STUDY), did not use a device intended for consumers but rather sensors designed for professional use, which is a more reliable method for detecting atrial fibrillation. Furthermore, the study focused on individuals with risk factors for a heart attack. Unsurprisingly, the detection (and treatment) of atrial fibrillation tripled, but despite this setup, the study found no benefit in terms of a reduction in heart attacks or arterial embolisms.Some experts believe that there are different types of atrial fibrillation and that we simply do not yet know how to distinguish the dangerous types from the benign ones.In summary, it can be said (also based on some more recent data) that the benefit of the Body Scan ECG appears to be small. The benefit is likely to be significant only in high-risk population groups who are unlikely to use a €400 smart scale (e.g. the elderly).It is not yet known (as such devices have not become widely adopted amongst consumers) what the burden on the healthcare system is due to false-positive results. It is also worth noting that there is currently no digital infrastructure in place to enable the data generated by the scales to be transferred to a doctor for review. In fact, there is not even a standardised file format. Whilst there is an open data transfer standard (DICOM) for X-rays and similar imaging data, there is no equivalent for ECG data. All of the above explains why the Body Scan is not yet available in the US. The FDA has not approved it as a medical device. The regulatory frameworks and requirements differ between the EU and the US, but according to Withings, the Body Scan will become available in the US from the third quarter of 2023, following FDA approval. In Europe, the device ‘only’ needs to obtain the CE mark for medical devices. To obtain the CE mark, the device must meet certain standards, which depend on its classification. Body Scan is classified as a Class IIA device (which, interestingly, places it alongside dental fillings, surgical clamps and tracheostomy tubes). Conformity assessment is not carried out by the European Medicines Agency (EMA) but by independent accredited organisations (known as ‘Notified Bodies’). They analyse and certify the device’s safety and performance. Approval by the EMA and the FDA is essential, as it is naturally important to have independent confirmation that the device actually detects the arrhythmias it claims to detect, and so on. Here is a YouTube video from Medlife Crisis discussing the benefits of atrial fibrillation screening. The video focuses on the Apple Watch, but in principle the same applies to any consumer device: https://www.youtube.com/watch?v=rW3DGnHO2iY&t=719s DETERMINING BODY COMPOSITIONBody composition data is extremely useful for assessing your health and fitness levels. An easier measure to use is the body mass index (BMI), which requires only your height and weight to calculate: (weight in kilograms)/(height in metres²). Although BMI correlates with health, there are many exceptions, particularly concerning very fit individuals with a high amount of muscle mass (who are often technically overweight), and lean individuals with little muscle mass (who are not technically overweight but may still have too much body fat). A much better measure of fitness is body fat percentage, which this scale determines using bioelectrical impedance analysis (BIA). The scale measures the percentages of fat and muscle mass in the torso and other body parts. Put simply, this means that the scales send electrical impulses through the body. As fat conducts electricity less efficiently than muscle, the scales can deduce the amount of fat between two measurement points. Unfortunately, BIA is not a particularly accurate method for determining segmental body composition. To truly know where the fat is located, and in particular to distinguish between visceral and subcutaneous fat, the gold standard is magnetic resonance imaging (MRI). At present, however, this method is rarely used for this purpose outside of medical research, and it is also very expensive. A less accurate method for measuring body fat percentage is dual-energy X-ray absorptiometry (DEXA/DXA), which is primarily used to determine bone mineral density, but which can also be used to measure body fat percentage. However, DEXA has difficulty distinguishing between subcutaneous fat and visceral fat (if you wish to have this type of analysis carried out, you should ask your service provider what data their device provides). To obtain segmental body composition data, you’ll need a smart scale from the Body Scan range. The Body Comp and Body Smart models do not offer this feature. The big question is: how do the scales carry out this measurement, and how reliable is it? There isn’t much information available, except that the scales use multiple frequencies to improve measurement accuracy. Thanks to the BMI calculated from the arms and legs, the segmental body composition is probably reasonably accurate. However, it is completely unclear how the scales determine the percentage of visceral fat. There are no explanations, patents or – most importantly – scientific publications that would validate the technology against the gold standard of MRI. The percentage of visceral fat is also displayed separately from body composition, which may suggest that this measurement is taken using a different method. Paradoxically, the legendary six-pack is not a good indicator of fitness: if there is fat covering the six-pack muscles, you cannot see the six-pack, even if it is there. However, the fat covering the muscles is not the most dangerous type of fat. The dangerous fat is found beneath the six-pack muscles, in the body cavity where your organs are located. You may have a visible six-pack despite the fact that dangerous fat has accumulated on and around your vital organs (liver, kidneys, intestines, etc.). The body fat percentage determined by the scales is probably reasonably accurate. However, without external validation, I suspect that the visceral fat index shown to me by the scales is nowhere near a meaningful value in reality. What does this ‘visceral fat index’ actually mean? According to the explanation, it is a value between 1 and 20. But what is it? I would understand if body fat percentage were broken down into visceral and non-visceral fat (but that figure would be between 0–100 per cent). As long as it remains shrouded in obscurity, this value is likely to be rather useless (and I’ve seen it fluctuate quite rapidly from one day to the next, which suggests it isn’t very reliable). ASSESSING THE RISK OF CARDIOVASCULAR DISEASEWhen it comes to cardiovascular disease, the three major risk factors are:

Body Scan on Michael’s Domain

Withings Body Scan smart scales