DEXA Scan Body Composition (review)
I was recently approached with the opportunity to get a free DEXA body composition test from DEXA SCAN. A DEXA (Dual-energy X-ray Absorptiometry) is the gold standard for body composition testing. I’ve actually been very curious to get this done ever since I learned about it in my nutrition classes. I consider myself to be a healthy weight, but the idea of getting my entire body slowly scanned like a giant piece of paper, and then sharing that information on the internet was a little daunting. I can’t say I’ve ever cared to know what my skeletal system looks like, but at least now I know I could have a thigh gap if I had zero body fat (joking, don’t ever make that a goal).
What DEXA measures:
- Fat (and how you carry it)
- Bone Density
This handy chart from ACE fitness shows body fat % ranges for men and women. I measured 24.3% body fat (region %fat), which just barely slides me into the “fitness” range. To get that body fat % number, you take the measured fat (lbs) divided by total mass (lbs) 32.68#fat/134.2#total=24.3% body fat. The sheet also shows my (tissue %fat) as 25.3%, which is my body fat % if you subtracted out the weight of my bones, but that’s not what body fat % charts are giving ranges for–it’s region %fat. Essential fat for women is 10-13%, and 2-5% for men, so when evaluating yourself make sure you remember that some fat is essential for life and proper hormone production. I would love to shave off a few lbs of fat this marathon training and get re-tested lower in the “athlete” range around 20% body fat, roughly 7# lost, while still maintaining my 97 lbs of lean mass. The goal with weight loss should be fat loss, not just dropping numbers on the scale. A diet containing adequate calories, protein, and the addition of strength training is key for maintaining lean mass with weight loss, especially if your goal is to decrease body fat.
I have a handheld BIA (bio-electric impedance analysis) body fat testing device, but it’s typically +/- 3% off in accuracy, which is identical to the body fat testing a lot of home scales have built-in now. A BIA device sends a faint electrical signal into your body and uses an equation based on how much resistance it detects. Electricity readily flows through muscle, but not fat, so hydration levels can be an accuracy factor with BIA. The BIA cannot detect internal fat around your organs, so it tends to measure body fat % lower than a DEXA. I tested my body fat % with the BIA device immediately after getting the DEXA, and I was 1.5% lower body fat with the BIA, which was expected. In general BIA devices work fine for tracking long term changes in body fat, but they won’t be able to tell you specific information like where you carry your fat, or bone density. If you care about knowing EXACTLY what your muscle mass, fat mass, and bone density are, a DEXA scan will show you all of that in detail.
The scan will also show whether you carry fat more around your midsection (android fat) or around your hips/butt (gynoid fat)–the classic apple or pear shape. Carrying higher amounts of android fat increases your risk for metabolic diseases like diabetes, and cardiovascular disease. I do own a mirror, so I already knew that I carry more weight in my hips than my midsection, but the DEXA confirmed it. You want your android/gynoid fat ratio to be less than 1, and mine is 0.73, so I’m in the target range.
The DEXA also shows your bone density; I was a slightly above normal. I guess I can thank running and strength training for keeping my bones strong. I was surprised my skeleton only weighs 4.89 lbs, with my skull being the most dense (gotta protect that huge brain, right).
So overall, it was fun to see my numbers, and I would get another one if I felt like I had significant body composition changes. The Lamkin Clinic in Edmond runs $175 where I had mine done, so it’s not something you would pay to have done very often. I would not say it’s not something you absolutely HAVE to get done to track weight loss or body fat lost. How your clothes fit, how you look in the mirror, and how you feel about your fitness level, are terrific indicators of your progress. But, if you want to get into the fine details of your body composition, then the DEXA scan will show you that.
So what do you think, would you get a DEXA scan?
Disclaimer: I was not paid to write this review, but I was given a free DEXA in exchange for reviewing my experience on the blog. The opinions are all my own.