A few days before Thanksgiving, I scheduled an appointment for a DEXA scan to measure my body composition. I’ve estimated my body fat percentage to be in the range of 20-22% range just based on comparisons with online pictures, but I wanted to know more definitively where I stood.
DEXA scans are considered the gold standard now for body composition and are far more accurate than bioimpedance (used in many home scales now) and caliper testing.
There is some controversy regarding the accuracy of DEXA vs the hydrostatic method (water dunking), but I liked the convenience of getting a DEXA scan.
This is a picture of what the machine looks like. You basically lay on the table and do you best to hold still, while that L-shaped wand scans over your body. It’s basically a human copy machine.
The whole process takes about 10 minutes and at the end they give you a print out which I’ll go over below.
There are two main draw backs to DEXA scans.
The first is the price. In some locations, it can cost up to $450, which is prohibitively expensive. The average price from a brief search online was in the $100 – $250 range, which I felt was still out of my price range for a test that isn’t essential. Having knowledge of body composition is helpful, but serial abdominal circumference measurements while not as accurate, if viewed through the lens of long term trends, can be just as useful.
Luckily someone on paleohacks pointed me in the direction of The Exercise and Metabolic Disease Research Laboratory in UCLA that performs DEXAs for the very affordable price of $50.
The second draw back is radiation exposure. The technology is based on using X-rays to detect how dense different parts of your body are, and using these density measurements to calculate your body composition. Here is a table comparing the amount of radiation compared to other Radiologic procedures, and as you can see the radiation exposure is pretty minimal, coming out to less than 0.5% of the exposure seen with a Chest X-ray.
It’s also been said that the amount of radiation is less than the radiation you are exposed to when flying from California to New York. Despite the low radiation dose, it’s still not a procedure I’d get more than once every couple of years.
Here are my results:
This first page provides an overview of the scan on the left with an image of my skeletal structure and of the soft tissues of my body. All the white in the soft tissue diagram represents fat! Just eyeballing it, you can see that most of the fat is located around my hips, thighs, and butt… which pretty much confirms the BJJ Cavewife’s observations.
The table on the bottom right goes over the bone mineral density (BMD) of the various parts of my body with a composite total number on the bottom (circled). My total BMD is 1.264 g/cm2. This is plotted on the multicolor graph in the top right. I’m clearly in the ‘blue’ area which is average… where as the ‘green’ area would be optimal. Looks like I have to up my intake of vitamin D.
[otw_is sidebar=otw-sidebar-1]
This second page is pretty much where the money is at! The scanner itself has a scale which measured my weight as 186.8 lbs. When I measured my AM weight on my home scale that morning it was 183.8 lbs. The difference in weight is easily explained because I normally weigh myself only in my boxers, whereas on the DEXA machine I was fully clothed.
The DEXA measured my total amount of body fat at 49.39 lbs, making my body fat percentage 27.4%. This was pretty surprising to me since it was much higher than what I was expecting, but I guess that is the benefit of obtaining an objective measurement, I now know exactly how much fat I’m carrying around.
The benefit is that I also know exactly how much lean weight I have, 130 lbs, which will make calculations for my desired protein intake more accurate (although calculating my exact macro intake is one of the things I most dislike about tracking).
The table in the middle goes over my fat distribution, with 29.3% as Android fat (abdominal) and 31.6% as Gynoid fat (hips and butt)… which we already know about!
The color chart on the bottom right shows that I’m right smack dab in the yellow ‘overweight’ range.
This last page details the composition of each individual body part. The technician who went over this exam with me told me that people who are right dominant usually have about 0.5 lbs more muscle and 0.5 lbs more fat on their dominant side. So the right hand of someone who is right handed will weigh about 1 lb more than their left hand. The thing that jumped out at me most was the difference in lean mass between my right leg and my left leg of almost 1.5 lbs. This corresponds to my being right leg dominant. Looks like I’ll have to do more left legged pistols to balance things out.
The bottom part of the page goes over how much ‘visceral fat’ I have which is 0.76 lbs. The technician told me that under 3 lbs is optimal, so I’m doing well here. Visceral fat (fat surrounding the internal organs) is the bad fat and is associated with insulin resistance, diabetes, and metabolic syndrome among a host of other things.
And in case you’re wondering what 27% body fat actually looks like, these were pictures I took right after I got home.
So, the main takeaways from this are that:
- I’m fatter than I thought which sucks, but at least I now know unequivocally where I stand and how much further I have to go. If I’m able to lose 25 lbs of fat that will bring me down to 15.5% body fat which would be optimal.
- I need to increase my intake of Vitamin D to hopefully get my BMD in the optimal range.
- I need to start doing more exercises to strengthen my left leg in order to balance things out.
UPDATE 2/6/2014
According to Tammy who actually works in this lab:
Please refer to your region % for total body fat, since this value includes bone mass for total body. The tissue % only contains fat & muscle, no bones. The region % is more accurate.
My Total Region % Body Fat = 26.4%
While this is slightly better… I still have quite a ways to go!
Thanks for chiming in Tammy!
UPDATE 10/21/2014
Just checked the new website for the UCLA Exercise Physiology and Metabolic Disease Research Laboratory and can’t seem to find any information on whether or not they still offer DEXA and metabolic testing. If you’re interested in going there try contacting them at:
(310) 825-8499 or via e-mail at info@uclaemdr.org
Cool test! I’m going to look around for a $50 one locally.
Nice! Let us know how it goes for you!
just a comment on the diff between your legs…
is it possible that you have one leg shorter than the other, this is not uncommon, & usually totally unnoticed.
you may be able to tell visually by standing in front of a mirror barefoot & touching the bone on the top of each hip to see if they are horizontal or not.
in the scan itself you seem to be ‘lent over’ slightly, which could be just the way you were lying, or could be another indicator of the leg thing.
& finally in the photo it also looks like you have a slight sideways lean (could just be the photo angle as well).
Very astute observation. I’ve seen a physical therapist before and he told me that I had ‘right lateralization,’ where part of me is shifted to the right… as you pointed out.
You can see that my pelvis is slightly tilted up on the right, while my right shoulder is slightly tilted down.
I never notice these things when I look in the mirror, but it really shows when I see pictures of myself.
I was given exercises to do… which I’ve been really bad at doing. I know I know… naughty naughty!
I think the appearance of me in the scanner is just with how I ended up lying down. I was trying to follow the directions of the technologist, but it’s actually hard when you’re lying flat and don’t have any sense as to the markings on the table.
Regarding the leg shortness thing. I never measured my leg lengths before, but an interesting thing is that if you look at the bone mineral content (BMC) on the last page, you can see the bone mineral of right leg weighs 1.29 lbs and my left leg weighs 1.20 lbs, which isn’t much of a difference, but again, I’m not sure how much this relates to leg length.
Another thing I’ve noticed is that my right foot is larger than my left. When I try on new shoes, the right shoe always feels tighter… which in my mind supports the finding that my right leg is overall stronger than my left.
I just got my Dexa scan done last week in Chicago and Quad’s Gym at 3727 N. Broadway. $175 for initial scan and a follow up scan or $100 for one scan. If I can change 5% in 90 days I get a third scan free.
I was horrified to see my total BF%. The whole reason I went was to get a “real” baseline number. I also wanted to verify against my home scale that I have had for years. My home scale was only off by 1.2%. It was higher.
So I can state that you can trust your Tanita bio impedance scales. Wake up, use the bathroom and then weigh in. This is assuming you maintain a consistent level of hydration from day to day.
My Tanita scale repeatedly told me 21-22% in the AM.. and was pretty off!
You’re getting serial DEXAs? Despite the low level of radiation, it might not be something you want to get that regularly. Maybe a bodpod would work better if you’re going to measure every couple of months… or even just measuring body circumference at multiple sites.
Thanks for your thoughtful comments btw!
I was at 19.6% bodyfat and I followed a ketogenic diet. It took 8 weeks to lose 5% of bodyfat to reach 14.4%. I did dexa scans both at the beginning and at the end of the experiment.
I find them very accurate and objective as well. Check my blog if you want to read about my experiment!
Chris! Dexa confirmed a fat loss of 5% in 8 weeks? Are you kidding me? I would kill for that! I am older, 45 and fatter at 38.8% per Dexa. I am really hoping I get those results. 2 weeks in doing Carb Nite. Tonight is my second Carb Nite. I checked the 2nd morning after last Carb Nite and was .03 mm on blood ketones, but this morning after 8 days no carbs I was 1.5 mm which was better. I believe my two home BF tests may be confirming a 1% loss of fat in about 10 pounds total weight so far. I will be checking the blog now.
Great looking website! Loved your post… you seem to have had great results.
Your blood glucose pre-keto also seemed to be in a very good range.
Guys…any idea on when blood sugar could improve? Although now overweight again, I am a fairly active mountain biker. I can now confirm I am also pre-diabetic with fasting ranges over 100. 130 the morning after carb nite. Sobering reality. I approached researching this with the theory I was already insulin resistant.
So far down approx. 8-10 pounds, lost 1% bodyfat, feel better. Also noticing mood/personality changes, probably from sugar being gone as well as gluten. Its a lifestyle change. Planning, shopping, learning to cook, but I am not stopping.
Congrats on the weight loss thus far! Have you been measuring with body circumference?
Also good that you’re trying to adopt it as a lifestyle… I think that’s the best way to approach this.
My blood sugars have almost always been in the 80’s whenever I am in ketosis confirmed with blood ketones. Are you checking your blood ketone levels?
Since the strips are so pricey, I will only be checking blood levels weekly. The first test was .5mm but keep in mind this was the second morning after my first carb night (fasted). The second ketone check was the morning of my second carb nite (fasted) and I was at 1.5mm.
They say the sweet spot is 1.5 to 3.0 as far as fat burning and calling it nutritional ketosis. I believe Jimmy Moore may have said ketones are higher in the p.m. but you must wait till X number of hours after a meal.
So far the biggest issue is trying to eat more than 1800-2000 calories! I am aware metabolism could slow, so I am trying to avoid a huge caloric deficit, but the lack of hunger is simply amazing and consistent.
How often are you testing your blood sugars?
My blood sugars 2-3 times a week first thing when I wake up.
I got a Myotape which I thought would be more accurate, but trying to measure around my love handles and stomach seems too variable.
I’d imagine it will take you 6-8 weeks for blood sugars to come back down… it’s probably the first time you’re giving your pancreas a break in quite a while.
I like the myotape. The trick is to always measure it in the same spot, which is why I picked the belly button.
You can do what Tim Ferriss recommends and measure in multiple locations, both biceps, both thighs, hips at widest portion, belly button level, chest, and even neck. Then add them all up, and that will be your total inches for the week.
Takes a lot of time though, but more accurate than the bio-impedance measurements.
Thanks for coming by our lab and writing a detailed commentary about your experience. We wish you luck with your continued body goals.
Thanks for stopping by! I’m happy you found my writeup.
Hi,
I actually work at the EMDR lab where you had your DXA scan. Please refer to your region % for total body fat, since this value includes bone mass for total body. The tissue % only contains fat & muscle, no bones. The region % is more accurate.
Thanks
Thanks! Just updated the post.
Sweet. I am glad I found this. I get a DEXA scan next week and am doing a second phase of NK here in New Zealand. I’m also trying to measure as many other metrics as possible to get an overall picture. When I get my scan I may just ask you a few questions if you don’t mind.
Thanks for all the info.
Feel free to ask any time…. hopefully I’ll have a good answer for you!