Body Fat Percentage
body-metricThe proportion of total body mass composed of fat.
Definition
The proportion of total body mass composed of fat. Measured by DEXA, hydrostatic weighing, or skin fold calipers. Healthy ranges: men 10-20%, women 18-28%. A more accurate health indicator than BMI.
What Is Body Fat Percentage?
Body fat percentage is the proportion of total body weight that is composed of adipose (fat) tissue, expressed as a percentage. Unlike BMI, which uses only height and weight, body fat percentage directly quantifies fat mass versus lean mass, making it a more precise indicator of body composition and metabolic health. It includes both essential fat (necessary for hormonal function, organ protection, and neurological health) and storage fat (energy reserves held in adipose tissue).
Measurement Methods
Several techniques exist with varying degrees of accuracy and accessibility:
- DEXA (Dual-Energy X-ray Absorptiometry): Gold standard for research; provides regional body composition data with an error margin of approximately 1–2%.
- Hydrostatic Weighing: Underwater weighing based on body density; accurate but requires specialized equipment.
- Skinfold Calipers: Pinch measurements at multiple sites fed into population-specific equations; accessible but technique-dependent.
- Bioelectrical Impedance Analysis (BIA): Sends a low electrical current through the body; practical for consumer devices but sensitive to hydration status.
- Air Displacement Plethysmography (Bod Pod): Measures body volume via air displacement; comparable accuracy to hydrostatic weighing.
Healthy Ranges and Why They Matter
Healthy body fat ranges differ by sex because women require more essential fat for reproductive hormonal function:
- Men: Essential fat 2–5%; athlete 6–13%; fitness 14–17%; acceptable 18–24%; obese 25%+
- Women: Essential fat 10–13%; athlete 14–20%; fitness 21–24%; acceptable 25–31%; obese 32%+
Excess body fat, particularly visceral fat surrounding abdominal organs, is strongly associated with insulin resistance, type 2 diabetes, cardiovascular disease, and systemic inflammation. Conversely, body fat below essential levels impairs hormone production, immune function, and bone density. Monitoring body fat percentage over time provides a clearer picture of training and dietary progress than scale weight alone.
Related Guides
Related Terms
BMI (Body Mass Index)
A screening tool calculated as weight(kg) / height(m)^2.
Lean Body Mass (LBM)
Total body weight minus fat mass, including muscle, bone, organs, and water.
Visceral Fat
Fat stored within the abdominal cavity around internal organs (liver, pancreas, intestines).
Subcutaneous Fat
Fat stored just beneath the skin.