The Difference Between a DEXA Scan and an InBody, and How to Choose
This is a question I get constantly. They’ve heard that a DEXA scan is the gold standard for body composition, they’ve seen the InBody standing in the corner at Ivy Health Clinic, and they want to know whether the one we use is the good one or just the convenient one.
These two tests aren't competing with each other, they were built to answer different questions. Once you know which question you're actually asking, the choice gets simple.
What a DEXA Scan Does
DEXA stands for dual-energy X-ray absorptiometry. It was built to measure bone mineral density, and that is still the thing it does better than anything else on the market. It is the diagnostic standard for osteoporosis.
Modern DEXA machines also estimate body fat percentage, lean mass, regional fat distribution and visceral fat. You lie still on a table for roughly ten to twenty minutes while low-dose X-rays pass through you.
If you plan to compare DEXA results over time, the testing conditions matter as much as the machine does. Use the same machine every time, book the same time of day, arrive well hydrated, skip hard training for the 24 hours beforehand, and eat roughly the same way before each scan. Without that consistency you are measuring the conditions, not your progress.
What the InBody 580 Does
The InBody 580 is a professional-grade analyzer that uses multi-frequency bioelectrical impedance. You stand on it, hold the hand electrodes, and in under a minute you are done. No radiation, no table, no gown.
It reports body fat percentage, skeletal muscle mass, lean body mass, segmental muscle and fat analysis across your arms, legs and trunk, visceral fat level, total body water split into intracellular and extracellular, basal metabolic rate, and phase angle.
Side by Side Comparison:
| Measure | What it means | DEXA scan | InBody 580 |
|---|---|---|---|
| Body fat percentage | How much of your body weight comes from body fat rather than muscle, bone and water. | ✓ | ✓ |
| Skeletal muscle mass | The amount of muscle you have and can gain or lose over time. | ✓ | ✓ |
| Segmental analysis | Shows muscle mass separately for each arm, leg and your trunk. | Limited | Detailed |
| Visceral fat | Fat stored around your internal organs rather than under your skin. | Estimated | ✓ |
| Body water | Total body water, including water inside and outside your cells. | — | ✓ |
| Basal metabolic rate | An estimate of the calories your body burns at complete rest. | Limited | ✓ |
| Bone mineral density | Measures bone strength to assess osteoporosis and fracture risk. | ✓ (Gold Standard) | — |
| Radiation exposure | Whether the test uses X-rays. | Low-dose X-ray | None |
| Test time | Typical time needed to complete the scan. | 10–20 minutes | About 60 seconds |
| Practical retest frequency | How often it is realistic to repeat the test. | Occasional | Every 4–8 weeks |
When a DEXA Scan is the Right Call
Bone health. That is the one thing an InBody can’t touch, and it’s not a small thing.
DEXA is the diagnostic standard for bone mineral density, which is the measure used to assess osteoporosis and fracture risk. An InBody doesn’t measure bone and was never built to, so if a DEXA has been recommended to you, an InBody is not a substitute.
If bone density is what you’re after, ask your doctor about a referral. There are also private clinics in Kelowna that will scan you without one, and you can email hello@ivyhealthclinic.com for a recommendation on where to go.
When the InBody is the Better Fit
If the question is whether you are losing fat or losing muscle, whether your strength training is doing anything, or whether your midsection is changing at all, the InBody answers it in sixty seconds and then answers it again six weeks later.
The ability to retest quickly and easily is why we have an InBody inside Ivy Clinic.
I use these numbers to make decisions. If skeletal muscle mass has dropped while your weight decreased, we raise protein and change how you are lifting. When visceral fat is moving but the scale hasn’t budged, you get to see the plan is working instead of thinking you haven’t made any progress. When one leg is carrying noticeably more lean mass than the other, that changes your program.
Those are calls I can’t make from a bathroom scale.
If you’re losing weight on a GLP-1 medication, tracking gets more important rather than less. Some absolute muscle loss comes with any meaningful weight loss. What’s worth watching is your skeletal muscle mass ratio, and that ratio is the number that matters more than the raw kilograms.
The Midlife Piece
This is where the segmental numbers earn their keep.
A five-year study published in Maturitas in 2020 followed 489 women aged 40 to 79, scanning them with DEXA in year one and again in year five. Two findings are worth your attention:
Through the forties, fat mass climbed: total fat mass, arm fat mass and leg fat mass all rose significantly, while lean mass held and in places went up.
From the fifties, arm lean mass began dropping, earlier and by more than anywhere else in the body. The authors point straight at what that means for how you train.
So what you’re watching depends on where you’re standing. In your forties the fat mass climbs while the muscle holds, and from your fifties the arms start to go. A bathroom scale shows you neither, because those numbers can move in opposite directions and still land on the same weight.
The InBody breaks arm lean mass out separately from legs and trunk, which means we can catch that shift while it’s happening instead of six months after you noticed your sleeves fit differently. When it shows up, we increase protein on the days you lift, along with the volume of upper body exercises, then re-scan in six weeks to see whether the numbers move. There is more on what changes underneath in perimenopause if you’re curious.
Consistency Beats Precision
Most people ask which test is the most accurate. The more useful question is which test you’ll repeat.
Whether your body fat reads 31% or 32% matters far less than knowing it has come down steadily across six months. One perfect number tells you where you are standing. A series of consistent numbers tells you which direction you are moving, which is the more important metric.
The research backs this up. McLester and colleagues put three InBody analyzers head to head against DEXA in the Journal of Clinical Densitometry in 2020 and found small individual measurement error across all of them, concluding the devices can stand in when a DEXA is not available. They also flagged a systematic bias in every comparison, including a proportional bias for fat mass in women specifically.
That matters less than it sounds. A consistent bias shifts your absolute number and leaves the direction alone, and direction is what we adjust against.
Why We Use the InBody 580 at Ivy Health Clinic
Because we can scan every six weeks without thinking twice. When a measurement is quick, safe and cheap enough to repeat, it becomes part of how the plan gets adjusted rather than a snapshot you file away and forget about.
It is also honest about its limits. It does not measure bone. It will not hand you a research-grade absolute number. What it gives you is a reliable direction, measured the same way every time.
What You Do With the Results Matters
Say your skeletal muscle mass came down four hundred grams. On its own, that’s a number on a page.
What I want to know is whether you are under-eating protein on the days you lift, whether the drop came from your arms and your program has no pulling in it, or whether you have been training hard on five hours of sleep for a month. Your scan gets read by someone who already knows your training and your food, so the number turns into something you change on Monday.
Then we adjust what we’re doing and scan again in six weeks to find out whether the change worked. That loop is what you’re booking, and it is why these numbers live inside nutrition and fitness coaching.
If you’ve been doing everything right and the scale won’t tell you why you’re not making progress, an InBody will at least tell you what is changing. Come get a baseline and let's see what we’re working with.
Book an InBody 580 scan | See what the scan measures
Frequently Asked Questions
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For bone mineral density, yes. DEXA is the diagnostic standard and an InBody does not measure bone at all. For body composition, DEXA has lower measurement variability. Validation research shows InBody analyzers track changes in fat mass, muscle mass and body water reliably under consistent testing conditions, which is what matters when the goal is measuring progress across months rather than one absolute number.
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Not if bone health is the question. DEXA is a medical diagnostic test used to assess bone mineral density and fracture risk, and an InBody cannot substitute for it. If a DEXA has been recommended to you, follow that recommendation. For tracking fat loss, muscle gain, visceral fat and hydration over time, an InBody gives most people what they need. Ivy Health Clinic in Kelowna can point you toward a DEXA provider on request at hello@ivyhealthclinic.com.
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Every four to eight weeks suits most people. That window is long enough for real change to register and short enough to adjust the plan before progress stalls. Scanning weekly mostly measures hydration noise. At Ivy Health Clinic in Kelowna, scans are timed to coaching check-ins so the numbers arrive when there is something to do with them.
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Yes. The InBody measures electrical conductivity through body water, so hydration, meal timing and recent exercise all shift the reading. Keep the conditions consistent: same time of day, similar hydration, no hard training in the hours beforehand, and no food immediately before. Ivy Health Clinic sends a prep guide before your first scan.
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Yes. Unlimited InBody 580 scans are included with the Ivy League Premier membership at Ivy Health Clinic in Kelowna. Scans are also available as a standalone booking with no membership required, and membership is never required to access care at the clinic. Current membership details and pricing are available in Jane. Call 250-410-4406 or book at ivyhealthclinic.janeapp.com.
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The InBody sends a low-level electrical current through the body, and the manufacturer advises against testing anyone with a pacemaker or another implanted electronic medical device. Tell the team at Ivy Health Clinic before you book and they will direct you to the right person. Call 250-410-4406 in Kelowna with any questions.
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Ivy Health Clinic offers InBody 580 body composition scans at 202-2900 Pandosy Street in Pandosy Village, Kelowna, BC. The scan takes about 60 seconds and can be booked on its own or as part of nutrition and fitness coaching with Dawn Thalheimer, Health and Nutrition Coach. Current pricing is shown when you book online at ivyhealthclinic.janeapp.com, or call 250-410-4406.
This article is for educational purposes only and does not constitute medical advice. The information presented does not create a practitioner-patient relationship. Body composition testing is one tool among many. Speak with a qualified healthcare provider for personalized guidance about your health.
