{"id":2769,"date":"2026-06-26T15:00:13","date_gmt":"2026-06-26T15:00:13","guid":{"rendered":"https:\/\/silvybrand.com\/?p=2769"},"modified":"2026-06-26T15:00:13","modified_gmt":"2026-06-26T15:00:13","slug":"optimizer-withings-dexa-body-composition-health-fitness","status":"publish","type":"post","link":"https:\/\/silvybrand.com\/?p=2769","title":{"rendered":"Sometimes, health tracking accuracy is overrated"},"content":{"rendered":"


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This is <\/em>Optimizer<\/a>, a weekly newsletter sent from <\/em>Verge senior reviewer<\/em> Victoria Song<\/em><\/a> that dissects and discusses the latest gizmos and potions that swear they\u2019re going to change your life. Opt in for <\/em>Optimizer here<\/a>.<\/em><\/p>\n<\/div>\n

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About three years ago, a doctor told me I had to lose abdominal fat. She didn\u2019t care about my lower belly fat. That, she said while pinching me, was subcutaneous fat. What she wanted was for me to target about five pounds of fat loss above my belly button because that\u2019s where the visceral fat lived. Not weight loss; my BMI and weight, she said, were fine. I needed fat<\/em> loss because I had borderline high cholesterol and one mildly elevated liver enzyme. Given my diagnosis of polycystic ovary syndrome (now known as polyendocrine metabolic ovarian syndrome<\/a>), she was convinced that Type 2 diabetes lurked just around the corner for me unless I immediately overhauled my body composition.<\/p>\n<\/div>\n

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She suggested I invest in a smart scale \u2014 as well as commit to a vegan diet. I ignored the latter (and, a few months later, switched doctors after she recommended a dubious dieting podcast). But I did start dabbling a bit more seriously with smart scales, embarking on a multi-year journey of frustration.<\/p>\n<\/div>\n

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Smart scales use a method called bioelectric impedance analysis (BIA) to give you a breakdown of your body fat, lean mass, and bone mass. (Some high-tech smart scales include other metrics, but it depends on the device.) The gist is that a weak electrical current is sent through your body. Fat, muscle, and other types of tissue all have different levels of conductivity, so depending on the resistance measured, an algorithm then estimates how much of each you have. They\u2019re more accessible for consumers than other clinical methods, but they can be notoriously inaccurate. It\u2019s very easy to have two BIA scales and get wildly different results.<\/p>\n<\/div>\n

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If you do get a segmented body analysis scale, keep in mind they\u2019re not exactly cat-safe. Petey cannot resist the string.<\/em><\/figcaption><\/p>\n<\/div>\n<\/div>\n<\/div>\n
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Case in point, this morning I stepped on three separate smart scales: two from Withings (one only measures through your feet; the other has more advanced segmented body analysis), and a third from a company called Twin Health. When I go for my monthly doctor follow-ups, I get measured by an InBody scale, which is a fancier version of the smart scales people have at home. Two weeks ago, I went to a sports clinic to get my first Dual-Energy X-ray Absorptiometry (DEXA) scan, which shoots low-power X-rays through your body to provide a breakdown of your body composition, including bone density. It\u2019s often considered the \u201cgold standard\u201d in clinical settings. None of these devices has ever given me the same body fat percentage.<\/p>\n<\/div>\n

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In fact, here are my most recent readings for each scale:<\/p>\n<\/div>\n

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