Body Fat Percentage and the DEXA Scan

kazcat

New member
A nice reference of what 27% body fat looks like on a female

The pictures are from this morning, right before hopping in my car and heading to DexaFit Atlanta.

And more from within the past week

So today was a reality check. I just got back from my DEXA scan, and really learned a lot about my body this way. Highly recommend it.

Now, first of all, I had always felt that I looked like I was 20% body fat. I just didn't feel that I carried a lot of subcutaneous fat. Well using a DEXA scan is different from other body composition estimations in that it is a measurement rather than a calculation. oops, my bad. should have fact checked Dual-energy X-ray absorptiometry is great at measuring bone density and body fat, so you can actually split your weight into three categories: body fat, non-bone lean mass, and bone mass. Because this method measures body fat around your organs, in your joints, in your head, and whatnot, basically places you don't pinch and don't visually see, it will give you a number that's 2-5 points higher than what you would get using a caliper- but if you can get past the larger number, the benefit is that this method is much more accurate, and really, the main sources of error are not in measurement but in how closely the subject matches testing conditions across tests (for example, do it in the beginning of the day, fasted, properly hydrated, and on the same week of your menstrual cycle if applicable). It was determined that at my height and weight, since I am a relatively small person, the non-subcutaneous fat would have more of an impact on my BFP- so I was told that if I was estimating 20% visually, to expect a 25% measurement.

Instead, my result showed 27%, which would be the equivalent of me doing a caliper test and getting 22%. I was NOT happy. Then we went over the distribution. I have 3 lbs of fat and 10 lbs of lean mass in my arms; 10 lbs of fat and 30 lbs of lean mass in my legs; 2 lbs of fat and 6 lbs of lean mass in my android (stomach) region; 7.5 whopping lbs of FAT and 12 lbs of lean mass in my gynoid (hips and butt) region!!!!! My calculated android%/gynoid% ratio was .71, which he said was very low. Basically I learned even if I got my arms, legs, and abs super cut, I will never reach my initial target bfp because of my FAT ASS (just kidding, but my A/G gravitation would make it extremely difficult). My initial reaction: :'((((((((((( "Well what the hell do I do? LIPOSUCTION MY ASS???" (jk again) But doing this helped me realize that it's not really the number itself that matters (I still don't think I look like I'm 27.4% fat, even though now I know for sure I am), but the improvement and just the differences between measurements that should count for anything. Even if I never make it below 21% (16% for all the caliper ladies), I'll still feel like a 10!

I also learned two interesting things- I have some really dense bones! This is interesting because most Asians have low bone density, and yet mine is sitting prominently ABOVE the good n' healthy region, in the "AMAZEBALLS" section of the graph (I named it, I think it actually said "Excellent"). And surprisingly, even though I'm right handed and lift bigger on my right side, my left arm and leg both have more lean mass than my right side...

Overall, a really cool experience, and I'm going in for a follow-up scan in 6 months. They have this challenge where if you drop your bfp by 5% in 6 months (don't know if I'll be able to do it but I'm going to try my hardest! That's my ideal number anyway), you get a third scan free.

Have any other ladies gotten a DEXA scan before? What was your experience like? Did you number vary as much from your expectation or were you spot on in predicting it?
 
@kazcat Wow...shit...if you're 27% I must be at least 35%, and I'm trying to gain fat as well as muscle :/ (so I bruise less easily). That doesn't seem like a good idea any more. :( boo
 
@kazcat Oh wow. I'm the same height and weight. I'm more bottom heavy than you, though. Can I ask, what are your measurements? You have so much definition, I'm so surprised by that bf reading. I've been wanting to get one done, but they're so expensive where I live :/ I find it so interesting to see people with the same stats as me, thanks so much for showing us!
 
@lilbithmb Sure! Here are my measurements:

neck: 14"
waist: 26.5"
hips: 36.5"
right arm: 11.5"
left arm: 11.5"
right thigh: 20.5"
left thigh: 20.5"
 
@kazcat I got a DEXA scan done in August, and it showed that I had 31.5% body fat. Almost obese! It scared me so much. I don't even consider myself overweight. 5"2 at ~120lbs.

Does anyone know if I should be worried? Or is this the everything is okay alarm?
 
@dawn16 Typically, the body fat tables that categorize "athlete", "fit", "good", "acceptable", etc. are still derived from older equations that don't take all of your body fat into consideration. Because of this, DEXA scans calculate a number that is usually around 2-5 points higher than those equations, with more of an impact the smaller you are. Based on your height and weight, I would subtract 5-6% from your DEXA number and use that to look at those tables.
 
@kazcat Thanks! I also have PCOS and recently read a research paper on "thin PCOS". It said that they had much higher visceral fat than non-PCOS-ers, this also freaked me out!
 
@kazcat You look great! We are the exact height and weight, but you have much more definition than I . Would you mind giving me a glimpse into your routine, so I may strive for your awesomeness?? :)
 
@dawn16 Of course!

6 days a week I do starved state HIIT first thing in the morning (sorta starved-state.. I have SciVation Xtend about 20 minutes before)

6 nights a week I rotate through one of the following:
Chest/Shoulders/Triceps, Back/Biceps, Legs, Speed & Heavy Bagwork, Sparring, Total Body Circuit (lighter weight, higher reps)

On Sundays I'll just do a 30 minute jog in the mornings and do a stretch routine.
 
@kazcat You look really good, thanks for sharing the information. It was an interesting read. I don't know too much about BF% and I was wondering if you ladies can help answer my question; Why is it important to know the percentage this exactly? Too measure your progress? Could you measure your progress also with a less accurate method? I mean do the other measures show progress more or less correctly even if the absolute measure is not exact? Or are there other reasons why one would want to know the exact number of BF%?
 
@harris11651 There are several reasons. One might be to make sure you are within the healthy range (for women, 14-20% is considered athletic, 21-24% fitness, and 25-33% acceptable). You generally don't see many women below 20% unless they're training for a physique competition or are otherwise extremely serious about their level of fitness (which is another reason some people might track bf%). And some people find it a useful metric if their goal is weight loss, since you want to lose fat while maintaining your muscles. It can also be helpful in terms of achieving aesthetic goals.
 
@kazcat Do they not include the chest area as part of the breakdown. That area is likely to contribute a lot to your BF% because boobs. I think this tends to get overlooked ALOT when women get these types of scans.

You look great. Don't get too caught up in the numbers. As long as you like how you look and are healthy then take the numbers with a grain of salt. Quality > quantity IMO.
 
@sheron They have a section called "Trunk" which has two subsections, "Android" and "Gynoid", and I'm assuming the leftover is the chest region. When I factor out the Android and Gynoid parts, the rest of the trunk is 5.9 lbs of fat and 23 lbs of lean mass (and then an additional 1.1 lbs of bone) for a total of 30 lbs total. So including my boobs, my whole chest area is 19.7% body fat. I have small boobs. I'm a 32A. I've always had broad shoulders and rib cage- while I'm a 32 band size, my waist is 26.25 flexed and 28 relaxed. I think it probably factors into a pretty significant difference for most women, but for me my butt decided it didn't want to share the cornbread.
 
@kazcat Wow...as an x-ray/CT tech I'm really shocked that people are subjecting themselves to ionizing radiation to just measure body fat %. I had no idea that this is something done for cosmetic purposes, especially when there are other methods available to measure body fat.

While the dose is less than a round-trip cross country airline flight, radiation damage is cumulative and every little bit is harmful.

I would be very cautious about doing this, particularly if one flies frequently, lives in Colorado or other places with high background radiation, or has medical conditions warranting frequent x-rays and ct scans.

Also, if you are hoping to have children, realize that women have a finite number of eggs. Our eggs are very sensitive to ionizing radiation.
 
@kattale The technicians who perform the DEXA scans - thousands of times over the course of their careers - don't even shield themselves during the procedure. That's how tiny and insignificant the amount of radiation produced by DEXA is. It's very different from regular x-ray and CT. The amount of radiation experienced by a patient during DEXA is even lower than the normal background radiation you experience every day, let alone during a flight. There's no reason to freak people out about losing their eggs over this.
 
@nrnowlinma Yes, the techs are far enough away that they use distance as shielding. Knowing a lot about radiation, I just can't imagine exposing myself like that when there are other options. Sure, this one procedure is no biggie, but you are just adding unnecessary radiation on to the exposure we get anyway.
 
@kattale It's an interesting point you raise, but given the relatively few times that a woman might do this in her lifetime, I do believe this ranks in the very minor category. Also, knowing ones bone density and visceral fat % are really valuable pieces of health information to have and not in the vanity category by any means.

This is a total stretch, but for a woman at a healthy weight like OP (and many of us in here) I would venture to say that we will likely see the insides of hospitals far less than many obese Americans and as such are already far less likely to be subjected to risky Xrays and other medical tests/devices/procedures if we weren't at "healthy" weights. So in those terms, I'm totally willing to take this risk.
 
Back
Top