VISIFIT

The Comparison

DEXA vs. Every Other Method

A smart scale estimates. BMI measures no composition at all. Here is what each method actually reports, the margin of error published for it, and where it goes blind.

Book Your DEXA ScanWhat DEXA Measures

Why DEXA Wins

What can DEXA do that the alternatives cannot?

Three things, and none of them is simply a tighter number. It resolves fat, lean tissue and bone separately for each region of the body; it reports bone mineral density; and it puts a figure on the fat around your organs. BIA, Bod Pod, calipers and BMI do none of the three.

±1–2% Margin of Error

The precision hospitals and research institutions rely on — and the standard other methods get measured against.

Full Regional Breakdown

See fat, muscle, and bone data for arms, legs, trunk — left vs. right.

Visceral Fat + Bone Density

The only accessible method that estimates visceral fat and measures bone mineral density.

Side by Side

Body Composition Methods Compared

A detailed comparison of the five most common body composition measurement methods.

DEXA Scan

Gold Standard
Margin of error:±1–2%Duration:Under 2 minutes

Fat, lean mass, bone density, visceral fat (estimated), regional analysis

Pros

  • Gold standard accuracy
  • Full-body regional breakdown
  • Bone density measurement
  • Visceral fat estimate
  • Highly reproducible results

Cons

  • Requires clinic visit
  • Minimal radiation exposure

BIA (Smart Scales)

Margin of error:±3–8%Duration:Instant

Estimated body fat %, lean mass, water

Pros

  • Convenient at-home use
  • Low cost
  • Quick readings

Cons

  • Results vary with hydration
  • No regional breakdown
  • No bone density
  • No visceral fat estimate
  • Inconsistent between devices

Bod Pod

Margin of error:±2–3%Duration:5-10 minutes

Body fat %, lean mass

Pros

  • No radiation
  • Relatively accurate

Cons

  • Affected by clothing and air temp
  • No regional analysis
  • No bone density
  • No visceral fat estimate
  • Limited availability

Skinfold Calipers

Margin of error:±3–4%Duration:10-15 minutes

Estimated body fat % (subcutaneous only)

Pros

  • Low cost
  • Portable

Cons

  • Highly operator-dependent
  • Only measures subcutaneous fat
  • No visceral fat or bone density
  • Poor reproducibility
  • Uncomfortable for some

BMI Calculation

Margin of error:Not measuredDuration:Instant

Weight-to-height ratio only

Pros

  • Free and simple
  • Universally known

Cons

  • Cannot distinguish fat from muscle
  • Misleading for athletes
  • No body composition data
  • No bone or visceral fat info
  • Outdated as a health metric

Margins of error are the ranges published in the literature for each method, not a measured figure for any one device. Reproducibility also depends on the operator and on scanning under consistent conditions.

HOLOGIC DEXA technology is trusted by NFL, NBA, and MLB teams, leading hospitals, university athletic programs, and research institutions worldwide.

A whole-body scan delivers about 3 µSv — less than a single day of natural background radiation, and a fraction of a transcontinental flight.

Common Questions

DEXA vs. Alternatives FAQ

Why is DEXA more accurate than BIA smart scales?

BIA (Bioelectrical Impedance Analysis) passes a small alternating current between electrodes and infers fat from the resistance it meets. That resistance moves with hydration, meal timing, skin temperature and even damp feet, which is why the published margin runs ±3–8%. DEXA reads tissue directly from how two X-ray energies are attenuated, at ±1–2%, and it is the method against which the others are validated.

Is a Bod Pod better than DEXA?

Bod Pod measures body volume by air displacement and comes close on precision (±2–3%). What it cannot do is separate subcutaneous from visceral fat, measure bone density, or break results down by region. DEXA does all three, which is what makes the report actionable rather than just a single percentage.

Why shouldn't I just use BMI?

BMI divides weight by height squared and stops there. Muscle and fat weigh into it identically, so a lean athlete and a sedentary person of the same height and weight land in the same category. DEXA reports the fat, lean tissue and bone behind that one number, and where on the body each of them sits.

How much does a DEXA scan cost compared to other methods?

A scan here starts at $149, against roughly thirty dollars for a consumer smart scale and nothing at all for a BMI calculation. The difference is not only the margin of error: BIA and BMI return one estimated percentage, while a DEXA report carries fat and lean mass per region, bone mineral density with T-Score and Z-Score, and an estimate of visceral fat.

Measure it instead of estimating it

Direct tissue measurement on a clinical HOLOGIC Horizon-A, region by region, in under 2 minutes.

Safe • Painless • Under 2 Minutes
Book Your DEXA Scan