DEXA Body Composition Scan: What to Expect, How it Works, & Why it Matters

April 10, 2026

Understanding your body's composition is essential in today's health-conscious world. With the growing need for accurate analysis, a DEXA body composition scan stands out as the gold standard for assessing body composition. This page will guide you through what a DEXA scan is, how it works, preparation tips, understanding results, and its benefits.

What is a DEXA Body Composition Scan?

DEXA stands for Dual-Energy X-ray Absorptiometry. It's a specialised scan used to measure fat mass, lean mass, and bone density accurately. Unlike other methods, such as Body Mass Index (BMI) or callipers, the DEXA body composition scan provides detailed insights into your body's makeup. This is why it is considered the gold standard for accurate body composition analysis compared to any other method.

How Does a DEXA Body Composition Scan Work?

The technology behind a body composition scan involves using X-ray beams that pass through your body. The data collected from these beams is then analysed to provide comprehensive insights into your body's composition. One of the key advantages of this method is its safety; the radiation exposure during a DEXA scan is minimal.

How to Prepare for a DEXA Body Scan

To prepare for a DEXA body scan, wear comfortable clothing without metal fastenings and avoid eating for at least two hours before your appointment. The scan itself takes about 10-20 minutes and involves lying still on a table while the scanner passes over your body. Rest assured that all safety protocols are strictly followed during the procedure.

Understanding Your Results: How to Read a DEXA Scan

Learning how to read DEXA scan results for your body composition can be enlightening. The results will show percentages of fat, muscle mass, and bone density. Healthy ranges vary by individual factors, such as age and gender, but generally speaking, red flags include excessively high or low values in any category.

Benefits of Regular DEXA Body Composition Scans

Regularly undergoing a DEXA body composition scan offers numerous benefits, including monitoring fat loss progress and tracking muscle gain. Additionally, it provides insights into bone health, which can help tailor fitness and nutrition programmes specifically suited to your needs.

The Importance of DEXA Scans for Bone and Body Health

Bone Density and DEXA Scans

The bone density aspect of a DEXA scan is particularly important for ageing adults, women over 50, athletes, and others at risk of osteoporosis. Maintaining good bone health is critical not only for longevity but also for preventing injuries.

Tracking Body Fat Percentage with a DEXA Scan

DEXA scans for body fat percentages offer precise measurements of both subcutaneous and visceral fat. Tracking these metrics can be invaluable for those on fat loss journeys or those looking to maintain optimal health levels.

Is a DEXA Body Composition Scan Right for You?

Whether your goals involve peak athletic performance, proactive health management, or simply embarking on a successful fat loss journey, a DEXA scan provides invaluable insights.

For Athletes

A DEXA scan can precisely measure lean muscle mass, fat mass, and bone density in different regions of the body. This detailed breakdown allows athletes to:



  • Identify muscle imbalances that may hinder performance or increase the risk of injury.
  • Track the effectiveness of training programs and nutrition strategies by observing changes in muscle and fat distribution.
  • Understand their body composition in relation to the specific demands of their sport, which helps refine training to enhance power, endurance, or agility.


Concerned About Osteoporosis Risks

Osteoporosis, a condition characterised by weak and brittle bones, is a significant health concern, particularly as we age. A DEXA scan is the best way to measure bone mineral density (BMD). By providing a precise reading of BMD, a DEXA scan can:


  • Diagnose osteoporosis or osteopenia (a precursor to osteoporosis) before a fracture occurs.
  • Assess an individual's risk of future fractures.
  • Monitor the effectiveness of treatments for osteoporosis over time.
  • Help individuals make informed lifestyle choices regarding diet and exercise to maintain bone health.

On a Fat Loss Journey

For anyone focused on weight management and fat loss, a DEXA scan offers a more accurate and comprehensive picture than traditional scales or BMI. It distinguishes between fat mass and lean mass, allowing you to:


  • Accurately track fat loss and muscle gain, rather than just overall weight changes.
  • Identify stubborn fat areas and understand how your body responds to dietary and exercise interventions.
  • Set realistic and achievable body composition goals, moving beyond the limitations of simply "losing weight."

Your Questions Answered

  • Can I eat before a DEXA scan?

    Yes, you can eat before a DEXA scan. There's no need to fast.

  • How does a DEXA scan work for body composition?

    A DEXA scan, or Dual-Energy X-ray Absorptiometry scan, uses low-level X-rays to measure body composition. It works by sending two different energy levels of X-rays through your body. These X-rays are absorbed differently by bones, fat, and other tissues. The scan then creates a detailed image showing how much of your body is made up of bone, fat, and lean tissue. This helps in understanding your body composition more accurately.

  • How often should I get a DEXA body composition scan?

    Regular DEXA body composition scans are generally advised every one to two years to monitor changes. However, this is a general guideline, and your doctor should determine the optimal frequency for these scans. Your physician will consider your individual health profile, including pre-existing conditions, specific health goals, and risk factors for conditions such as osteoporosis or sarcopenia, to recommend a scanning schedule that best suits your needs.

  • Is a DEXA scan painful?

    A DEXA scan is not painful. You lie still while the machine takes images.

  • How accurate are DEXA Scan results?

    DEXA scan results are very accurate for measuring bone density and body composition. However, like any test, there's always a small margin of error.

Book Your DEXA Scan Today

Contact our clinic online and book an appointment for a DEXA scan with our team in Sydney today! At Specialist Medical Imaging, we’re passionate about providing accessible healthcare to all, which is why we offer walk-in same-day services at our Grose Street, Parramatta site for your convenience. We also accept all referral forms, including those from other radiology practices, making it easy for you to receive the reliable health services you need.