Yesterday I went for a DEXA scen to get an accurate picture of body fat, bone density, do a VO2 test and get all my resting metabolism stats done. I used Dexafit and it’s SUPER useful if you’re interested in this kind of stuff. I had been thrilled that my at home body fat scale was at 20%; well, it turns out by body fat is actually 32!!! A really unpleasant wake-up call. as part of the VO2 testing, they do what’s called an RER, respiratory exchange rate, that tells you where you’re pulling your energy from, glucose or fat. Mine showed 50/50 (a .85 machine reading). He said (and I later substantiated) that anyone in keto would have a .7- reading, meaning that they are pulling all of their energy from fat. That was another wake-up call. I am not in keto, even though my little sticks tell me that every morning and I’m sticking to strictly less than 15 carbs a day. The good news is that I can go back to Dexafit and keep track of this but it was a bit of a gut punch yesterday. I’m curious if anyone else has used this kind of testing and found it useful, surprising, etc…Also I’m of course wondering why keto strips say I’m in keto when i’m clearly not. (I am 56, female, 5’6" 130lbs, generally athletic, though resting this summer, so was very surprised/disheartened by the body fat number.)
RER rate showed not in Keto--anyone familiar? (Geeky body stat stuff)
How long have you been eating keto? Your RER will continue to improve over time. Also, what did you eat the night before (or day OF) the test? Were you fasted? For how long? There a lot of factors. 
You can be in ketosis (as shows by your sticks - or more accurately by blood) but not be fully fat adapted yet. The longer you eat this way, the more fat adapted you’ll become and the more your body will rely on fat (which will reflect as a higher RER). My RER was very high because I’ve been fat adapted for almost 1.5 years.
Don’t stress. KCKO.
Curious - what was your V02?
Thanks. FYI, I am 56, female, 5’6" 130lbs, generally athletic, though resting this summer, so was very surprised/disheartened by the body fat number. I have not been working out as hard as usual but have generally considered myself fit. Ha. I feel almost embarrassed to go back to the gym!
My VO2 was 30.5. The really good thing was my anaerobic threshold was162 but other than that, blech. I have only been on keto for less than 2 months and only tracking intake with app (KetoDietApp) since August 1, so not long at all. I was fasting–had just had black decaf. I had a tuna nicoise salad the night before.
Yeah, if you haven’t been working out, and have only been keto for two months, Expecting a high fat, low carb RER is not realistic. Get running again when you’re ready, and KCKO.
As to the difference between your home scale and the dexa, what’s your process on the scale, and does it have an athletic setting?
Good news is you have a good baseline. You can track your progress.
The ketostix will tell you how hydrated you are and that is really all they ever told me. I got a cheap breathalyzer and never peed on another stick.
Don’t sweat this
Keep doing what you are doing!
I had a similar “ discrepancy “ as well
Dexa vs InBody Scan
In fact , I had my Dexa then went to get the InBody Scan…so it was within hours lol
So far off w results
I may get the Vo2 next time and or the RMR
Just to get all geeked out😂
Urine sticks are pretty useless for telling you if you are actually in ketosis ( obviously you found that out!).
I thought I was, too…for about a whole year! Pee sticks couldn’t have been any higher on the scale but I wasn’t losing any more weight or inches. Then I got MY wake up call and started blood testing both glucose and ketones: ha ha! .2 ketones! Whichh meant I wasn’t even close. Talk about shocked.
So I basically had to “re-learn” everything about keto, test for bg triggers, and eventually got it figured out.
Now I am a typical .7ish. Except this morning was 2.7 (and no logical reason I know of!)