Dexa scan

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Dexa scan recently completed at BodyScanUK

I recently got myself a DEXA scan!!!

What is DEXA scan? Dexa stands for Dual energy x-ray absorptiometry. A Dexa scan is big machine, similar to an MRI scan, except you have an ‘arm’ over you when lying on the bed, as opposed to being totally covered up. See the picture of me on the Dexa machine below.

DEXA scan will measure:

  • bone mineral density (BMD)
  • estimate of % body fat
  • fat-free mass (FFM)

Dexa scan machine

Not only does it measure your body fat, it also shows you where you store your fat across your body. You then get a nifty report that displays all your measurements & recordings. You can also see your scores compared to that of the general population matched for your age. Some of the readings you get include:

  • weight of your skeleton
  • weight of your fat mass
  • weight of your fat-free mass (lean mass including: organs, muscle, ligaments)
  • how much fat you store in your mid-section & how much you store in the hip/thigh area (android vs gynoid)
  • difference in your visceral fat to your subcutaneous fat

How to measure ‘Weight’ / Mass / Fat?

As the article HERE points out, there are a number of ways that you can measure and track changes in weight. Weighing scales provide a good guide to overall weight loss, although it’s not without it’s drawbacks. The weight that you hope to lose e.g. an excess of fat tissue, may be fat mass OR fat-free mass, and fat-free mass includes muscle. Ideally, we don’t lose muscle and we lose fat mass.

Example: Over an 8-week period for example, one client I worked with – by providing some simple & effective nutrition guidelines, and nothing overly complex – lost 1.6kg of ‘weight’ i.e. on the scales, she was only 1.6kg lighter. However, her waist circumference had decreased by 2 inches, and her hip circumference by 4 inches!!! We had not taken a Dexa scan, nor had we done skinfold’s or BIA. However, my assumption would be that her fat mass had decreased, and her fat-free mass (e.g. muscle) had increased, thus accounting for a minimal change on overall weight, as shown on the scales, yet an overall much better body composition and aesthetic look. This is what you’re aiming!

HERE is another interesting article about measuring weight changes, this time using a DEXA or BodPod (from the team at Examine)

So, weighing scales may provide a good guide, and can help to track large changes in weight, but are not able to accurately report what ‘stuff’ is actually being lost and can’t account for the more subtle differences in bodily change. Other methods to measure changes in body composition would include Calipers, Bioelectrical Impedance Analysis (BIA) and BodPod.


Bone density scan

Dexa scan – sometimes referred to as a bone density scan – can be used in the diagnosis and treatment of Osteoporosis. The Dexa scan measures bone density, and can therefore provide a good indication of the health & state of an individuals bone strength. This may be pertinent to women post menopause, when there has been a dramatic decline in peak bone mass. People of both sexes can suffer from osteoporosis, however, and so individuals past the age of ~50 may be inclined to have a Dexa scan.

Increasing bone strength: there are many ways to improve bone density & bone strength, and thus reduce the chances of fractures after a fall. These might include:

  1. greater intake of calcium – from foods like dairy, whole oily fish, nuts, vegetables
  2. greater intake of vitamin D – from greater sun exposure of supplementary Vitamin D
  3. weight-bearing or resistance exercise – over time will help increase bone density (and slow the deterioration in muscle loss)

Dexa scan results

Dexa scan summary
Me & my results

% body fat = 16.8

Lean mass = 61kg

Bone mass = 2.4kg

Fat mass index = 4.23

These are a selection of scores from the many that you receive in your very own personalised report.

I got the Dexa scan done at BodyScanUK. The clinic is based in London, a 2 minute walk from Regent’s Park, and not far from Harley Street. Phil, the owner, is a great guy, and if you book the hour consultation with the scan, he’ll take you through your results step by step. This I HIGHLY recommend – the detail Phil goes into brings the report to life.

Summary: a great experience and a novel opportunity. If you’re looking for an accurate way to measure body composition, or want an accurate method to track progress over a weight loss or weight gain intervention period, then Dexa scan seems by far and away the most reliable.