Who Should Get a DEXA Scan?
Author: Sabila S., MBBS
Medically reviewed by: Dr Sam Botchey, MBBS, MSc, FFSEM, MRCEM
A DEXA scan is a body composition tool primarily used by healthy adults to track fat loss, muscle gain, or healthy ageing. While it provides a clearer picture of where you are starting from, it is not suitable for everyone.
For most adults, a scan can generally be booked without a clinical referral. However, it is not recommended for pregnant women. Additionally, anyone seeking a diagnostic assessment for osteoporosis, or anyone with underlying bone health concerns, should consult their GP for a clinical bone density scan rather than booking a private composition assessment.
This article explores who is best suited for this technology, what you can realistically learn from the data, and the circumstances where seeking clinical advice is recommended before booking.
Who Tends to Get the Most from a DEXA Scan?
DEXA is useful across a broad range of goals. The common thread is that it can provide measurements that go beyond what weight alone shows: a breakdown of how much of your body is fat, how much is lean tissue, and where that tissue sits across different regions of the body.
People who want an objective baseline. If you are about to start a new training programme, change your diet, or make any significant lifestyle shift focused on body composition, a DEXA scan can provide an objective starting point. Rather than relying solely on weight or how you look in the mirror, you will have a set of figures you can return to after a few months to assess what has changed and where. This baseline can help you assess whether your efforts are producing the changes you are working towards when you return for a follow-up scan.
People working on fat loss. Weight loss is rarely a linear process, and the scales can be misleading. A DEXA scan gives you two separate measurements: one for fat mass and another for lean mass. This lets you see whether the weight lost on the scales came from fat, lean tissue, or both, a distinction that matters when your goal is fat reduction while preserving muscle.
People focused on building muscle or body recomposition. If your goal is to add lean mass, whether through resistance training, changes in nutrition, or a combination of the two, a DEXA scan may help you assess whether your training is producing the body composition changes you are working towards. DEXA scans can show you not only where lean mass has developed, but also whether that development is broadly balanced across different areas of the body.
People prioritising healthy ageing. As we age, preserving muscle mass becomes increasingly important for mobility and physical function. Some people also find the whole-body bone-related outputs useful as part of broader health tracking. However, a body composition DEXA scan is not a substitute for a diagnostic bone density assessment for osteoporosis or fracture risk. If that is your primary concern, your GP is the correct starting point.
Athletes and performance-focused individuals. For athletes, the distribution of lean mass can be just as important as the total amount. DEXA provides regional breakdowns, showing how muscle is distributed across the arms, legs, and trunk. For example, if an injury has led to muscle loss on one side of the body, repeat scans can help track whether that imbalance is improving over time. Tracking composition across multiple training blocks or competitive seasons can also help identify whether programming changes are producing the expected adaptations.
What Will a DEXA Scan Actually Show You?
A DEXA scan measures more than body fat alone. Here is what a typical report includes:
Fat Mass: The total weight of fat in your body, often broken down into regional areas such as the trunk or limbs.
Lean Mass: This includes your muscles, organs, and body water. Lean mass figures can give useful context for understanding physical strength and overall health, particularly when tracked over time.
Bone Mineral Content: A measurement of the mineral density of your bones across the whole body.
Regional Distribution: Data on where you carry fat (i.e., android vs gynoid). Android (central/abdominal) fat distribution is generally associated with a different health profile than gynoid (hip/thigh) distribution.
Visceral Fat: An estimate of the amount of fat surrounding your organs. Elevated visceral fat is generally considered relevant to metabolic health, and this figure can be useful to discuss with a healthcare professional.
A single scan gives you a snapshot of current body composition. Scans are most useful for tracking changes over time when taken under consistent conditions — ideally at the same time of day, after avoiding a heavy meal for around four hours, and with hydration kept normal and consistent.
WHAT THE SCAN DOES NOT TELL YOU A body composition DEXA is not a diagnostic scan and does not diagnose any medical condition. The bone data it provides is informative, but it is not equivalent to a clinical bone density assessment for osteoporosis or fracture risk. Results are most meaningful when tracked over time with a consistent preparation approach. |
When Is It Worth Speaking to a Clinician First?
While DEXA is considered a low-risk, non-invasive procedure for most adults, there are certain situations where it is advisable to postpone a scan or seek medical guidance before booking.
Pregnancy. DEXA involves a small amount of ionising radiation, and for this reason, it is not recommended during pregnancy. If you are pregnant, believe you may be pregnant, or have recently become pregnant, please do not proceed with a scan until you have spoken with your clinician or midwife.
Diagnostic bone health concerns. If your primary concern is bone density, osteoporosis or fracture risk rather than body composition, it is worth speaking with your GP first. Your GP can refer you to a specialist for a diagnostic bone density scan if they consider it appropriate. A body composition DEXA can provide some bone-related data, but it is not designed or validated to replace a clinical bone density assessment for diagnostic purposes.
Recent medical procedures or implants. If you have recently undergone imaging that used contrast agents, such as a barium swallow or certain CT scans, it is generally advisable to allow at least two weeks before booking a DEXA scan, though your provider can advise based on the type of procedure. These substances can temporarily affect how your tissues absorb X-rays, potentially influencing your results.
If you have medical hardware such as a pacemaker or joint replacement, it is worth contacting your provider before booking. They can advise whether this is likely to affect your suitability for the scan and how results may need to be interpreted.
Active health conditions. Conditions that affect body fluid levels, muscle mass or metabolic function, such as oedema, certain kidney conditions or active inflammatory diseases, can influence how DEXA results are interpreted. In these cases, a DEXA scan can still be useful, but it is best discussed with a healthcare professional who can help place the results in the context of your overall health.
Is One Scan Enough, or Should You Track Over Time?
A common question for those wondering who should get a DEXA scan is how often they should return. While a single scan offers immediate clarity on your current body composition, its greatest value is found in trend tracking.
A single scan has limits. Without a comparison point, it is harder to assess progress or identify trends. The figures you receive are most actionable when you can observe how they change in response to training, nutrition or lifestyle adjustments over a period of months.
For many people, spacing scans roughly every twelve weeks may allow enough time for detectable changes to become apparent. Scanning too frequently may lead to frustration, as small day-to-day variations in hydration or food intake can cause minor fluctuations in the data that do not reflect true changes in body composition.
What to Think About Before You Book
If you have decided that a DEXA scan aligns with your goals, a small amount of preparation will help ensure your results are as useful as possible.
Define your goal: Are you looking to lose fat, build muscle, or simply monitor your health? Knowing this helps you and your consultant interpret the data effectively.
Prioritise consistency: If you plan to track your progress, try to use the same provider and scanner for follow-up appointments.
Follow preparation guidelines: Try to arrive in a similar state each time, avoiding a heavy meal for around four hours beforehand, keeping hydration normal and consistent, and avoiding hard exercise in the 24 hours before your appointment.
Disclose your history: Always mention any recent medical imaging, metal implants or health concerns to your technician before the scan starts.
Conclusion
A DEXA scan can be a practical and informative tool for a wide range of people, including those working towards fat loss, building muscle, monitoring changes as they age, or wanting a clearer sense of their current body composition. Most healthy adults are well-suited to having one.
While it is an accessible tool for most, it is most effective when used as part of a broader health strategy. If you have specific concerns about your bone density or an underlying medical condition, your GP remains the best starting point for clinical advice.
Your Next Steps To schedule a DEXA scan for a clinical assessment of your body composition, please review our available appointment times. → New to DEXA? Try using our body recomposition calculator as a starting point for finding your targets. → Book a Scan: Every Scanletics appointment includes a 35-minute consultation with an expert to help you understand your results and what they mean for your goals. View our scan packages and book your appointment today → |
Sources
Nana A, Slater GJ, Stewart AD, Burke LM. Methodology review: using dual-energy X-ray absorptiometry (DXA) for the assessment of body composition in athletes and active people. Int J Sport Nutr Exerc Metab. 2015 Apr;25(2):198-215. doi: 10.1123/ijsnem.2013-0228. Epub 2014 Jul 14. PMID: 25029265. Cataldi D, Bennett JP, Quon BK, Leong L, Kelly TL, Binder AM, Evans WJ, Prado CM,
