I managed to get a random DEXA Scan a few days ago and decided to share comparative experience with other Garmin Index Scales owners.
1. Weight measurements - identical! At least Index does the primary job well.
2. BMC - bone mineral content. Index reports 4.7 kg, DXA scan shows ~3 kg. Might be some variation in 'what is a bone' and 'what is bone mineral content'. Never used this metric anyway.
Now Body Fat. This is a tough one.
When I set 'Activity Level' to honest number 8 (~10 hours a week), Index reports 7%.
When I set 'Activity Level' to 7, Body Fat rises to 9.5% (and bone content goes 0.2 kg down - WTF?)
I'm not sure I understand this metric in the same way as Garmin does. Manual says it is 'Visceral Fat', so I assume it means 'Belly Fat'.
However, DXA Scan shows 0.2 kg of fat in the Android area. The rest of fat tissue is so called 'Essential Fat' residing in arms, legs, trunk and gynoid area (totaling 6 kg, or 8.9% of full body mass).
The question is: what does Index measure? Visceral Fat? Then it is completely wrong. Total body fat? But manual says 'visceral', meaning 'belly fat'.
Verdict: one cannot trust 'Body Fat' metric.
Unfortunately, DXA scan does not show pure muscle mass (it shows 'lean tissue' which combines muscle with all the internal organs). But I would not expect Index Scale to report correct muscle mass.
Verdict: none of the advanced features work. Product was not worth the purchase. It's just a scale, nothing else. Worth $30 at most.
