Today’s bathroom scales can do a lot more than just measure your weight. Many have sensors that can be used to estimate your muscle mass and body fat, measure your heart rate, and even calculate your basal metabolic rate to keep track of your health or to help you.
These so-called Smart Scales use Bluetooth or Wi-Fi to synchronize all measurement data recorded about you with an app on your phone. Typically, this is the company’s app that creates the scale. In most cases, you can sync this data with Google Fit or Apple Health as well.
To make it easier for youLet’s go through the pros and cons of the best smart models on the market from Withings, Fitbit, Garmin, and others.
James Martin / CNET
What makes the Eufy Smart Scale so great is not just the scale itself, but also the app that goes with it. The app, available for iOS and Android, is very easy to navigate and provides detailed data and reports on weight, body fat, water, muscle mass, bone mass, BMI, BMR and more. The app also marks these measurements as low, normal, or high so you know how your health stats compare to what is considered the standard of health and fitness for your size and age.
The Eufy scale supports up to 16 different users in the app. Just select the right user in the Eufy app and all your data and metrics on the smart scale will be synced with that profile in the mobile app. It also connects to the Apple Health app and the Fitbit app.
James Martin / CNET
The Withings digital bathroom scale has many features that go beyond the rest. It includes detailed historical data and metrics on weight, BMI, body fat, muscle mass, body water, heart rate and bone mass, so you can see how these measurements, as well as your health and fitness, change over weeks, months, quarters and years. This Withings scale also records the weather every day you jump on the scale to help you decide what to wear when you step on the smart scale first thing in the morning.
The special thing about Body Cardio is that there are modes for pregnant women, babies and athletes, each tailored to the specific needs. If you want the smart scale to track your pregnancy, it will record your weight changes as your pregnancy progresses and suggest turning off body composition features that are not as accurate while you wear them.
In baby mode, you can hold your child and step on the smart scales to only measure their weight. Athlete mode is for professional athletes, bodybuilders, and anyone who weighs heavier because they have a lot of muscle mass and low body fat and BMI.
Two other bonuses: This bathroom scale uses a rechargeable battery (with a battery life of approximately 18 months) – many scales run on AA or AAA batteries – and supports up to eight different users.
Already using a Garmin fitness tracker? Then you might want to get a Garmin Index S2. This scale is an update to the index scale that I originally tested in 2019. Index S2 includes a new on-screen weight tracking feature that tracks changes in weight over the past 30 days after reading it.
The Garmin Connect app (Android and iOS) provides a holistic view of your health, including data and metrics such as activity level, weight, BMI, body fat percentage, and other measurements and data.
The smart scale measures weight, BMI, body fat, body water, muscle mass and bone mass, and provides accurate charts to track weight loss and other data over a week, month and year. It uses four AA batteries and has a battery life of up to nine months. Continue reading.
The Fitbit Aria Air is Fitbit’s newest smart scale and measures weight, BMI and body fat. These digital bathroom scales are best for people who currently have a Fitbit wearable and want to keep all of their data – activity, diet, weight, BMI, body fat, sleep – in one dashboard.
The Aria Air is an update to the Aria 2 that I tested last year. This Fitbit scale has a sleeker style and a new screen. As with the Air 2, you can have multiple profiles for different family members, and each of your metrics and data is stored in the Fitbit app (Android and iOS) in their user profiles.
The mistakes in measuring body fat with a scale
These intelligent scales go far beyond what a typical digital scale can offer. Each of them can measure your body composition, weight, and BMI using an electrical current that flows from the scale’s sensor through your leg, across your pelvis, and across your other leg. It measures how much resistance the current is encountering and then uses a mathematical formula to estimate how much fat, muscle, and bones make up your total weight.
While these functions are useful, they are not always reliable for measuring lean mass versus fat. Consumer reports tested the accuracy of many scales that measure BMI and body fat percentage and found that most underperformed when compared to a BodyPod – one of the gold standard clinical tests for body fat measurements.
Fat percentage data inaccuracies can be attributed to many things, such as: For example, if you are sick, hold water, have recently exercised, are menstruating, or have consumed alcohol. One of the most influential factors is where you carry your weight – if your chest and arms are slim, but you have more fat and muscle in your pelvis and legs, your total body fat percentage may be miscalculated.
Every smart scale I stepped on gave me a different percentage of body fat, but every number was within a 10% range. However, for percentage measurements of muscle mass, the range was between 33% and 63%. Two of the scales I tested provide a basal metabolic rate, but there was an incredible 631 calories difference between the two. That’s more than a McDonald’s Big Mac or three glazed Krispy Kreme donuts.
It’s also worth noting that BMI is not considered an accurate measure of body fat or general fitness. Hence, even correct BMI information should be ingested with a grain of salt.
All of this means you won’t get caught up in these metrics. For the most accurate measurements and data possible, follow the instructions that came with your smart scale. If you are concerned about your body fat percentage, body composition, health, or fitness, talk to your doctor about a proper scan. All of the models on this list of the best smart scales provide accurate readings of body weight – this is the single most important factor in your focus on weight loss. We will update this list regularly.
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The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a doctor or other qualified health care provider with any questions about a disease or health goals.