Your weight really doesn’t tell you all that much about your health. It fluctuates by several pounds throughout the day, making it difficult to get a truly accurate reading, and doesn’t account for more important measures like fat versus muscle mass. For that reason, a lot of us really only step on a scale when we visit a doctor.
Except, now there are scales that creators claim actually do account for these factors. Does that mean we should reconsider the scale after all? Not really.
Whether these scales can measure things like fat mass accurately is still up for debate, but medical professionals believe that they just aren’t accurate enough to be reliable. More than that, though, they still don’t determine what it actually means to be healthy.
Typically, “smart” scales work by incorporating metal electrodes upon their surface. When a person stands on them, the electrodes send a small electrical current through the body. Using this current, the scales can measure the resistance it experiences in the body. Muscle has less resistance to these currents, while fat has more. This has to do with the higher water quantity in muscle compared to fat.
By measuring this resistance, these scales can give a broad understanding of one’s muscle-to-fat ratio, which could indeed be a better assessment of one’s overall health than the commonly used Body Mass Index (or BMI). Because BMI is calculated using only one’s weight and height, it can neglect the fact that muscle weighs more than fat and therefore place people with significant muscle mass into the overweight or obese category, despite appearing physically fit.
Still, these scales don’t solve all of BMI’s problems. Namely, even someone with higher body fat who is categorized as overweight or obese by BMI can still be perfectly healthy on a cardiovascular level. More important than simply measuring how much fat you have is measuring where exactly you hold it — something smart scales are still largely incapable of doing.
For example, carrying fat in one’s midsection specifically does indeed correlate with developing health issues, especially pertaining to the heart. Meanwhile, thick thighs have been linked with greater overall health, and studies have found a correlation suggesting that women with big butts produce healthier children.
Some recently developed scales, like FitTrack, claim to be able to measure fat placement alongside other data points like hydration levels and protein intake. Whether this is accurate has yet to be independently studied. In all likelihood, any smart scale will indeed give you a broad picture of your overall measurements with some level of accuracy that may provide a more detailed look at your body than a regular scale could. But the thing is, these details could be just as arbitrary as your weight is, while becoming another stat to stress over. Beyond the word of your doctor, you might be better off focusing on how you feel and how you look — two things that are harder to measure, but are way more important to your overall sense of health.