How to lose fat sustainably doesn’t need to be a mystery – and the key is working with your body, not against it. 

Unlike online BMR calculators that don’t take body composition into account, a DEXA scan for body fat sets you up for long-term fat loss success via a precise estimation of your metabolic rate. If your New Year’s resolution or SMART goal includes body recomposition or fat loss, then this is the article for you.

In this article, we’ll take a look at what a DEXA scan is, answer some key DEXA FAQs, and offer a step-by-step guide to losing body fat using the results of a DEXA scan. 

What is a DEXA scan for body fat?

A DEXA (dual-energy X-ray absorptiometry) scan can be used for two main purposes: to measure bone density and to assess body composition. 

A DEXA scan passes two low-level X-ray beams over the body to create a high-resolution image – either of your spine or hip, (in the case of a bone density scan), or of your entire body (in the case of a body composition scan).

A DEXA scan is the gold standard in body composition analysis and gives you a detailed breakdown of total mass, percentage, and distribution of your body fat, lean mass, and visceral fat. You can read more about the body composition data that a DEXA provides in our blog article: What does a body composition scan show?

If you’re wondering how to measure body fat, a DEXA scan is the most accurate way to do so.  

How accurate are body composition scans?

The accuracy of a body composition scan depends on the type of scan in question. A DEXA scan is a precise and reliable way to assess your body composition. Unlike body fat scales – which utilise bioelectrical impedance analysis – a DEXA scan can measure levels of visceral fat, as well as offer a higher degree of accuracy for measuring body fat mass. 

How long does a DEXA scan take?

A DEXA scan is very efficient, taking approximately 4 minutes to complete. An appointment for a DEXA scan will typically be longer, including time for you to prepare for the scan and get changed, as well as time dedicated to talking through your DEXA results and crafting a personalised action plan. You can expect to spend approximately 45 minutes at your DEXA scan appointment. 

How much does a DEXA scan cost?

A single DEXA scan for body fat in the UK costs in the range of £125-200. Here at My Vital Metrics, our single scan DEXA for body composition costs £149, inclusive of your full DEXA report, complimentary 3D body scan, expert consultation, caloric estimate, and personalised action plan.  

The price of a DEXA scan will depend on whether the scan is for body composition, bone density, or both, as well as your location and choice of provider. 

Can a DEXA scan help me to lose body fat?

In short, yes! A DEXA scan for body fat can offer a great starting place for a range of fitness goals, including a goal to lose weight, lose body fat, or build lean muscle mass. 

How does a DEXA scan help with fat loss?

In addition to providing you with accurate data on your current body composition, including body fat percentage and visceral fat, a DEXA scan allows for an estimate of your basal metabolic rate (BMR). From this, we can calculate an appropriate calorie goal to facilitate fat loss. Knowing your body’s metabolic rate takes the guesswork out of calorie counting, and lets you create a reliable calorie deficit – essential for fat loss. 

What are the benefits of a DEXA scan for fat loss?

In addition to giving you an estimate of your metabolic rate, a DEXA scan also provides precise information on:

  • Fat mass and distribution
  • Visceral fat
  • Android: gynoid ratio
  • Fat-free body weight
  • Muscle mass and distribution
  • Muscular balance
  • Bone density 

This makes DEXA a powerful tool for a whole range of fitness goals, fat loss included.

How to use a DEXA scan to lose body fat

Now that we’ve outlined what a DEXA scan is and how it can help with a goal to lose body fat, let’s take a look at how to get started: 

Step 1: Book a DEXA scan for body composition

First, book a DEXA scan for body composition with a trusted provider. Make sure to check that the type of DEXA you’re booking is for body composition specifically – most services offer DEXA scans for bone density, but not body composition. 

Unlike medical DEXA scans, which tend to focus on a specific body area, a DEXA scan for body fat requires a scan of your entire body – make sure you opt for a provider who can offer this. Additionally, you’ll want to choose a provider who can give you unadjusted DEXA results. Some DEXA providers are still using an outdated calibration known as the NHANES calibration, which adjusts your results to add an additional 5% to your body fat measurement – this calibration has been shown to not be scientifically valid. 

At My Vital Metrics, we offer unadjusted DEXA scans for body composition, and bone density, and a combined option that lets you receive both sets of data from a single DEXA scan. 

Step 2: Receive your DEXA scan 

Next, attend your DEXA appointment. Once you arrive, you’ll be greeted by the DEXA technician, and asked a few questions about your overall health, as well as your fitness goals. 

When it’s time for your scan, you’ll be asked to remove clothing and any jewellery (you’ll be provided with a gown to wear), before lying on the DEXA scanner. The DEXA technician will position you on the bed, and the scan will take approximately 4 minutes to complete. A DEXA scan is a non-invasive, quiet, and painless procedure – and isn’t enclosed, so you won’t feel claustrophobic – simply lie back and wait for the scan to be complete. 

For more information on the DEXA scan procedure, you can watch our full explainer of how a DEXA scan works.

Step 3: Interpret your results


A sample DEXA body composition report.

Next, the provider of your DEXA scan will talk you through the details of your DEXA report

This will include a detailed breakdown of your body fat (percentage and distribution), lean mass, visceral fat, and (if you requested this option) bone density. The technician will be able to answer any questions you have about your results, and work with you to create a personalised action plan for meeting your fitness goals. 

Based on the information you receive, you might want to compare your results to a body fat percentage chart for your age and sex: 

My Vital Metrics body fat percentage chart for men and women.

Similarly, you can compare your visceral fat levels to a visceral fat chart to estimate your risk level:

The chart shows the visceral fat ranges that are considered to be "ideal", "at increased risk of cardiovascular disease", and "at high risk of cardiovascular disease", respectively.

Visceral fat is a crucial metric when considering your overall body fat percentage. Also known as “hidden” fat – as it largely isn’t visible unless measured directly – visceral fat is stored in our abdominal cavity, and high levels present a risk factor for heart disease, stroke, high cholesterol, and Type 2 diabetes. Regardless of whether you have fat loss as a goal, considering the visceral fat results from your DEXA scan is a great way to prioritise your overall health.  

Step 4: Set a calorie goal 

After you’ve received your DEXA results, the next step is to work with your provider to create a personalised action plan based on your health and fitness goals. 

For the goal of fat loss, this typically involves the creation of a personalised calorie goal. This begins with calculating your BMR (basal metabolic rate) and TDEE (total daily energy expenditure). 

Unlike a standard BMR and TDEE calculator that you can find online, working with the results of a DEXA scan lets you create a much more accurate caloric estimate. While online calculators take into account basic variables such as height, weight, and an estimate of activity level, our caloric needs vary considerably based on our body composition. 

To lose body fat, set a calorie goal that:

  • Creates a caloric deficit (this is a requirement for fat loss; consider 500 kcal daily)
  • Is no lower than your basal metabolic rate (BMR)/ resting metabolic rate (RMR)
  • Takes into account your activity level 
  • Is sustainable for at least 12 weeks 

Let’s consider a couple of examples of what this could look like in practice. 

Person A has a low level of muscle mass, is lightly active, has a BMR of 1200 and a TDEE of 1590, and has a goal of fat loss.

It would be difficult for Person A to create a significant caloric deficit without dipping below their BMR – which is medically unsafe. A good working solution here would be for Person A to increase their activity level, increasing their TDEE to ~1860. This would allow Person A to create a caloric deficit of 500 kcal daily by aiming for a calorie goal of 1360 kcal per day – still above their BMR. 

Person B has a higher level of muscle mass, is quite active, has a BMR of 1900 and a TDEE of 2945, and has a goal of fat loss. 

Person B has the space to create a significant caloric deficit without adjusting their current activity level. Creating a deficit of 500 kcal daily would give Person B a calorie goal of 2445 kcal per day. 

As with any fitness goal, it’s important to make sure that your caloric needs are personalised to your body and personal circumstances – and a DEXA scan for body composition makes that possible. 

Want to create a calorie goal, but aren’t able to get a DEXA scan?

Even if you don’t have the results of a DEXA scan or RMR test, you can still use our Basal Metabolic Rate and TDEE Calculator to provide an estimate of your caloric needs. Plus, if you have existing results from a DEXA scan or RMR, you can input these into the calculator to gain a more accurate caloric estimate. 

Step 5: Retest, reassess, and adapt accordingly

Once you have your calorie goal, it’s time to put it into action!

With any fat loss goal, it’s a smart idea to check-in on your progress regularly and adapt if you need to. If you aren’t noticing the results you’re hoping for, and you’ve been consistent for at least 4 weeks, it might be time to adapt your calorie goal. 

After 2 months, you can consider booking a repeat DEXA scan to view your progress! While 2 months is the minimum amount of time that’s safe for you to receive a repeat scan, the time frame will depend on your specific goals. Some people choose to receive a repeat scan after 3, 4, or 6 months. This is a great opportunity to celebrate  the results of your hard work, reassess your goals, and set new ones.  

Hit your fat loss goal with a DEXA scan at My Vital Metrics

A DEXA scan is the gold-standard in body composition testing, and is the best way to set yourself up for sustainable fat-loss success.  

Reach out to My Vital Metrics to book your free fitness consultation, or book a DEXA scan for body fat at My Vital Metrics today!