Body Composition Scanning Beyond Weight and BMI
Body composition scanning is a non-invasive method that uses 3D imaging and AI to capture precise health metrics from the human body, including body fat, lean mass, and metabolic indicators. Size Stream delivers these metrics from a single scan.
For health, wellness, weight loss, and clinical teams that need precise, repeatable body composition data, Size Stream delivers over a dozen metrics from a single scan. All metrics are built on a validated body measurement foundation, ensuring consistency across scans, users, and environments. Results are reliable from consumer weight loss applications through to professional and enterprise deployments. High precision and repeatability make the platform suitable for longitudinal tracking, clinical reporting, and population-level analyses.
Accuracy and Precision You Can Trust
Size Stream’s health metrics are generated using computer vision, machine learning, and AI models trained on large-scale body scan datasets. Every metric is derived from a standardized digital measurement process that delivers consistent, repeatable results while enabling organizations to capture body data faster, at lower cost, and at greater scale than traditional assessment methods.
- Consistent results across mobile and hardware capture methods
- High repeatability for longitudinal tracking and population-scale analysis
- Faster, standardized assessments with reduced labor and training requirements
- Scalable body data collection across clinics, research sites, wellness programs, and distributed populations
This combination of accuracy, operational efficiency, and scalability makes Size Stream well-suited for clinical research, health and wellness programs, remote monitoring, and enterprise deployments where consistent, repeatable body data is essential.
| Measurement | Variability / Error |
|---|---|
 Body Measures (avg of 46) | 0.60% |
 Body Fat Percentage | 1.50% |
 Max Waist Measurement | 2.6% |
 Body Fat Composition | 2.1 kg |
 Visceral Adipose Tissue | 0.19 kg |
 Body Mineral Content | 0.23 kg |
A Comprehensive View of Body Composition
Size Stream calculates a broad range of metrics from a single scan, covering how the body is structured, not just how much it weighs.
Body Composition
- Body Fat Percentage
- Lean Muscle Mass (Arms)
- Bone Mineral Content
- Lean Body Index (LBI)
- Lean Body Mass
- Lean Muscle Mass (Legs)
- Fat Mass Index (FMI)
Metabolic Indicators
- Resting Metabolic Rate (RMR)
- Body Surface Area (BSA)
Fat Distribution & Risk
- Visceral Adipose Tissue (VAT)
- Waist-to-Hip Ratio
- Waist-to-Height Ratio
Metabolic Health Indicators Without Invasive Testing
Understanding metabolic baseline is critical for health programs, weight management, and performance planning.
Size Stream provides metabolic health indicators derived directly from body composition scanning; no blood draws, lab tests, or clinical appointments required.
- Resting Metabolic Rate (RMR) — estimates baseline daily energy expenditure from body composition data, supporting personalized nutrition and training prescription.
- Body Surface Area (BSA) — supports clinical dosing calculations used in oncology and critical care, where treatment depends on body size.
Fat Distribution and Cardiovascular Risk Indicators
Where fat is stored is as clinically significant as how much fat exists. Visceral fat around abdominal organs carries higher metabolic and cardiovascular risk than subcutaneous fat beneath the skin. Size Stream captures these distribution patterns across the torso and abdomen, trackable over time, with no additional scanning required.
- Visceral Adipose Tissue (VAT)
- Waist-to-Height Ratio
- Waist-to-Hip Ratio
These indicators are associated with long-term metabolic and cardiovascular risk, providing health programs with objective, repeatable data that supports earlier intervention and clearer outcome measurement.
The Size Stream Fitness Index™: A Single Metric for Overall Health
The Size Stream Fitness Index is a composite metric that reflects overall health and fitness more accurately than BMI alone. BMI measures weight relative to height and nothing else. The Fitness Index incorporates muscle mass, fat distribution, body shape, and waist circumference. The result is a single score that captures meaningful differences between people with similar weight profiles.
The Fitness Index combines:
Built on a Validated Body Composition Scanning Platform
All health metrics are derived from Size Stream’s validated body composition scanning foundation. The same measurement engine that powers precise body data capture also governs every health metric output, ensuring consistency across scans, devices, and deployment contexts.
Body Composition Scanning as a Foundation for Health Intelligence
Size Stream’s health metrics serve as a structured data layer for health analysis, progress tracking, and personalization programs. By transforming raw body data into actionable health signals, organizations can deliver clearer insights, stronger engagement, and measurable long-term outcomes, without the cost, complexity, and health risks of lab-based assessments.
Frequently Asked Questions
What health metrics can a body scan provide?
A Size Stream body scan provides body fat percentage, lean body mass, lean muscle mass by limb, bone mineral content, visceral adipose tissue, waist-to-height ratio, waist-to-hip ratio, resting metabolic rate, body surface area, fat mass index, lean body index, and the composite Fitness Index score. All metrics are derived from one contactless scan, no additional tests or measurements required.
How is body composition measured without a lab?
Size Stream uses computer vision, machine learning, and AI to analyze body geometry from a 3D scan and generate body composition metrics directly from the scan data. The platform produces measurements and health insights, including body fat percentage, lean body mass, and visceral fat estimates, in minutes without a clinical setting, specialist operator, or invasive procedure. Additional health metrics, such as resting metabolic rate, are derived from these AI-generated body insights using validated calculation models. For a peer-reviewed comparison of 3D body scanning and laboratory body composition assessment, see the Size Stream white paper on mobile body composition assessment.
Can 3D scanning replace DEXA for body composition?
DEXA is the established clinical reference method. However, Size Stream delivers a rapid, scalable, non-ionizing assessment that is practical across consumer, wellness, and research settings where DEXA is not accessible or cost-effective. For longitudinal tracking, population screening, and program management at scale, body composition scanning delivers clinically relevant metrics at a fraction of the cost and complexity.
Talk to our team about 3D body scanning, fit, and body composition.