Body Composition Guide

DEXA vs InBody vs CALIPERS

Not all body composition tests are created equal. Here's how the most common methods compare—and why we use medical-grade DEXA.

COMPARISON AT A GLANCE

Method Accuracy Measures Visceral Fat Regional Breakdown Bone Density Cost
DEXA Scan Excellent
<2% error
Yes Yes Yes $100-200
InBody / BIA Moderate
5-8% error
Estimated Yes No $25-75
Calipers Variable
3-5% error
No No No $0-50
Smart Scale Poor
5-10%+ error
No No No $30-150 (device)
Hologic Horizon DEXA Scanner at Moonshot Medical

DEXA: THE GOLD STANDARD

DEXA (Dual-Energy X-Ray Absorptiometry) uses two low-dose X-ray beams to differentiate between bone, fat, and lean tissue. It's the same technology used in medical research and clinical trials.

Unlike other methods that estimate body fat, DEXA directly measures it. The result is precision that other methods simply can't match.

What DEXA Measures:

  • Total body fat percentage
  • Lean muscle mass (total and regional)
  • Bone mineral density
  • Visceral adipose tissue (VAT)
  • Fat distribution by body region
  • Left/right muscle symmetry

OUR EQUIPMENT

Hologic Horizon

The industry gold standard for bone density and body composition analysis.

Technology OnePass Fan Beam
Detectors 128 Ceramic
Scan Time <3 minutes (whole body)
Precision 4x better than standard
Max Patient Weight 500 lbs
Radiation Less than a flight

DEXA vs INBODY

DEXA body composition report

DEXA Report: Detailed regional breakdown

InBody scan results

InBody: Estimation-based results

How InBody Works

InBody and similar devices use Bioelectrical Impedance Analysis (BIA). They send a small electrical current through your body and measure resistance.

Fat conducts electricity poorly, so higher resistance = more fat. The device then uses algorithms to estimate body composition.

The problem: results are heavily influenced by hydration, food intake, and even the time of day. The same person can get significantly different readings hours apart.

Why DEXA is Better

  • + Direct measurement vs estimation
  • + Not affected by hydration status
  • + Measures visceral fat directly (InBody estimates)
  • + Bone density included (InBody can't measure)
  • + Consistent results for accurate tracking

Bottom line: InBody is convenient and affordable, but if you want to know your actual body fat percentage—not an estimate—DEXA is the answer.

OTHER METHODS

Skinfold Calipers

Calipers pinch skin at specific body sites to measure subcutaneous (under-skin) fat thickness. Results are plugged into equations to estimate total body fat.

Limitations:

  • • Only measures fat you can pinch
  • • Misses visceral fat entirely
  • • Highly operator-dependent
  • • Poor repeatability between testers
  • • Equations may not fit your body type

Smart Scales

Consumer scales with body fat features use the same BIA technology as InBody—but with far fewer sensors (usually just foot electrodes).

Limitations:

  • • Lowest accuracy of all methods
  • • Current only travels through lower body
  • • Wildly variable day-to-day
  • • Useful for trends only, not absolute numbers
  • • Can be off by 10% or more

WHEN TO USE EACH METHOD

Use DEXA when:

  • • You want accurate, actionable data
  • • You're tracking progress over months (cutting, bulking, recomp)
  • • You need to know your visceral fat levels
  • • You want bone density information
  • • You're making decisions based on your body composition

InBody/BIA is fine when:

  • • You just want a rough estimate
  • • You're tracking trends (using same device, same conditions)
  • • You don't need bone density
  • • Cost is the primary concern

Smart scales are useful for:

  • • Daily weight tracking (ignore the body fat %)
  • • General awareness of trends
  • • Motivation to stay consistent

GET YOUR BASELINE

Stop guessing. Get a medical-grade DEXA scan on our Hologic Horizon.

$150 | 15 minutes | Results same day

Book DEXA Scan