The full details of a Dexa Scan report

One of the core tests that we do at My Vital Metrics is the DEXA Scan – sometimes called just DXA. We’ve written a lot about this one test of course, because it is at the very centre of our services, because body composition is possibly the single most revealing set of statistics around a person’s health and their performance, if they are an athlete. 

 

In this blog post we are going to step through a full DEXA report, with all the things that we are able to extract from it, page by page. Hopefully it will give you a good sense of what a DEXA consultation looks like, and what kind of information you will get if you come to visit us in our lab in central London. 

 

Firstly, as we’ve discussed before: DEXA is what we call a 3-compartment model. This means that it separates the body into 3-compartments: Bone, Fat, and everything else, which is considered lean mass. In this it separates itself from many of the other methods which will measure only fat, or only body water, and assume standard values for the other compartments. 

 

With that in Mind, lets turn to the first page of the report, because this is the main page that’s all about bone density. 

This is critical, because all bone conditions are defined in terms of a T-score. A T-score of -1.5 is called osteopenia – thinning of the bones, and a T-Score of -2.5 or less is called osteoporosis. It should be noted that because we are doing full body scans, and we are not supervised by medical professionals, we are unable to diagnose such conditions directly. To get a formal diagnosis you would need to have a DEXA scan done of just your lumbar spine or your femur, under the supervision of a radiologist, and they would be able to offer a diagnosis and may suggest treatment. 

 

The second page, which will only come up upon your second Dexa scan and beyond, will show progress of bone density. These figures will go up and down, so it is overall trends we are looking for, and don’t expect any double-digit changes here – 1-2% either way is about the most I’d usually expect between scans. 

the next page of the report is where we start to get into the body composition, and the first figure we’ll pull out here is the overall body fat %. There are ideal reference ranges body body fat, laid down by the American Council on Exercise (ACE), which is 8-20% for men and 15-32% for women. It is interesting to note that these ideal ranges are actually age independent.

Visceral fat is considered especially dangerous. Even small amounts extra is highly correlated with heart disease and a host of other metabolic and cardiovascular risk factors. It is measured 3 ways, in weight, in volume and in surface area. Oddly most of the studies have been based on surface area, and this is the figure we concentrate on. Anything below 100cm2 is considered normal. from 100cm2 to 160cm2 is considered increased risk of cardiovascular disease, and above 160cm2 is considered high risk.

 

If you come up high, we will go into some depth about lifestyle, as factors like sleep quality, stress, and alcohol are all factors which may disproportionately lead to increased visceral fat. Because of this, you may be lean, but still have a high visceral fat – and if that’s the case, it’s considered even worse.

 

Finally, on the body composition main page, we will look at the overall lean index. The Lean index is a little bit like the BMI (Body Mass Index) but it only counts ‘lean mass’ which effectively means it is only counting the muscle. Like BMI it is divided by height squared, so this figure measures how much muscle you have for your height. This means that it might be harder for tall people to bring this metric up. Generally more is better, and I usually like to see a figure above 16.8 for women, and 19.8 for men – but the context is key. For some lightly built people this may not be achievable, and we will see how this changes over time instead.

Onto the final page of the main report we see all the figures we have seen on previous pages, just laid out in one big table. 

 

We don’t go over old ground on this page, but instead will just focus on muscular balance. We look at the amount of muscle in the left arm, vs right arm, and in the left leg vs right leg. If they are more than 10% different left to right, we will point this out and discuss remedial actions. 

 

Lastly, when you come in for repeat scans, you get the following page, which shows you exactly how things have changed overall, and each time you’ve come in. Here we can see a young bodybuilder who has been going through a very obvious bulking and cutting cycle – so we are able to track how much lean mass he is putting on in the bulk, and how much fat mass, and how much lean and fat mass he is losing in his cut. As you can see, in this example, he’s done a really good job in each cycle of preserving some of his lean mass through the cut, and limiting the fat gain through the bulk. 

 

After the raw DEXA report, we then turn to the action blueprint which really brings it all together, and turns the figures into an action plan to guide your future efforts. That may be the topic of another post however. 

 

As ever, with all the above, your personal situation is all-important and context is key. We always try to stick to the best science, and will try not to get drawn on elements for which we feel this isn’t good scientific basis. 

 

If you’ve any questions about any of the above, please do get in touch.