- What is the US Navy body fat method?
- The US Navy body fat method estimates body fat percentage using circumference measurements: height, neck, and waist for men, plus hip circumference for women. It was developed by the US Department of Defense and is considered accurate within ±3-4%. The formula uses logarithmic calculations based on the relationship between body circumferences and fat distribution.
- How accurate is the BMI-based body fat estimate?
- The BMI-based body fat estimate uses the Deurenberg formula, which accounts for age and gender. It is less accurate than the Navy method—typically within ±5% for most adults. It tends to overestimate body fat in athletic individuals with higher muscle mass and may underestimate in older adults. It works best as a rough screening tool.
- What is a healthy body fat percentage?
- Healthy body fat ranges differ by gender. For men: Athletes 6-13%, Fitness 14-17%, Average 18-24%, Obese 25%+. For women: Athletes 14-20%, Fitness 21-24%, Average 25-31%, Obese 32%+. Essential fat (minimum needed for survival) is 2-5% for men and 10-13% for women. Healthy ranges also increase slightly with age.
- How do I measure my waist and neck for the Navy method?
- For the waist, measure at the narrowest point (typically at the navel for men, or the smallest circumference for women). For the neck, measure just below the larynx (Adam's apple) with the tape sloping slightly downward. For women, also measure the hips at the widest point. Keep the tape snug but not tight, and take measurements on bare skin.
- What is the difference between body fat percentage and BMI?
- BMI (Body Mass Index) is a ratio of weight to height and does not differentiate between fat and muscle. Body fat percentage measures the actual proportion of fat tissue in your body. A muscular person can have a high BMI but low body fat. Body fat percentage is a more accurate indicator of health and fitness than BMI alone.
- What is the most accurate way to measure body fat?
- The most accurate methods are DEXA scans (±1-2% accuracy), hydrostatic (underwater) weighing (±2%), and air displacement plethysmography (Bod Pod, ±2-3%). Skinfold calipers (±3-4%) and the US Navy method (±3-4%) are practical alternatives. Bioelectrical impedance scales are convenient but less accurate (±5-8%) and affected by hydration levels.