When it comes to tracking my health and fitness progress, body composition testing has always been one of my go-to tools. But after recently trying three different methods — DEXA, InBody, and a Hume scale with wrist band — I learned firsthand just how different the results can be… and why I’ll always trust DEXA above the rest.
The Day I Put Them to the Test
In the same week, I had a DEXA scan, stepped on an InBody machine, and used my at-home Hume scale/wrist band combo. Here’s what they told me:
- DEXA Scan: 22% body fat
- InBody: 12% body fat
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Hume Scale + Wrist Band: 14% body fat
That’s a 10% difference between the lowest and highest reading. And if you’ve ever tried to lose or gain body fat, you know that 10% is massive — it can be the difference between being classified as healthy, athletic, or underfat.
Why the Numbers Don’t Match
Here’s the truth: not all body composition tools measure the same way — or with the same accuracy.
- InBody and most home devices use bioelectrical impedance analysis (BIA), which sends a small electrical signal through your body. The device estimates fat and muscle mass based on how fast the signal travels. But hydration, food intake, skin temperature, and even the time of day can skew results.
- Hume scale/wrist band technology is a consumer-level version of BIA with added formulas for activity levels. While convenient, it’s still heavily dependent on user input and environmental factors, including hydration levels, timing and more. To put it in perspective my HUME wrist band recommended a 3:47AM measure accurately. WHOA!! Who wants to get up at 3:47AM to measure their body comp???
- DEXA (Dual-Energy X-ray Absorptiometry) uses low-dose X-ray technology to directly measure fat mass, lean mass, and bone mineral density. It doesn’t guess based on water levels or algorithms — it scans and measures with medical-grade precision.
The Power of DEXA Accuracy
The 22% from my DEXA scan wasn’t just a number — it came with a complete breakdown of:
Fat mass by region (arms, legs, trunk)
Lean muscle mass distribution
Bone density
Visceral fat (the dangerous fat around your organs)
That level of detail is what allows me to make targeted changes to my nutrition, training, and recovery. The other devices gave me a number. DEXA gave me a color coded map of my body showing the exact location of the fat on my body.
Why This Matters for Your Health Goals
If I had trusted the 12% from the InBody, I might have assumed I was already extremely lean and skipped making improvements I actually needed.
If I relied on the 14% from the Hume scale, I’d still be off by 8% from my true measurement.
With DEXA, I know exactly where I stand and can track changes with confidence — no guessing, no “good day” vs. “bad day” readings.
My Takeaway
Your body composition is too important to leave to chance. If you’re serious about tracking fat loss, muscle gain, or overall health, make DEXA your baseline. Use it every few months to measure progress, and let the other tools be quick check-ins, not your primary source of truth.
Ready to see your true numbers? Book your scan today at DEXASCAN.com and take the guesswork out of your health journey.
