Waist-to-Height Ratio — NHANES Microdata Derivation
No published paper provides sex- and age-stratified WHtR percentile tables for US adults. The CDC NHANES body measures examination collects waist circumference (BMXWAIST) and standing height (BMXHT) for all participants. Percentiles were derived as follows:
- Data: Three NHANES releases were used: 2015-2016 (
BMX_I / DEMO_I), 2017-March 2020 (P_BMX / P_DEMO), and 2021-2023 (BMX_L / DEMO_L). Adults aged 20 and over with complete waist and height measurements were included after filtering biologically impossible values (n ≈ 18,700). - Weights: MEC examination weights were applied:
WTMEC2YRfor 2015-2016 and 2021-2023;WTMECPRPfor the 2017-March 2020 release. Each cycle's weight was divided by 3 before pooling to give equal contribution across cycles. No CDC-prescribed pooling method exists for this combination of releases. - Pandemic discontinuity: CDC advises caution when combining the 2021-2023 cycle with earlier cycles due to a 1.5-year fieldwork gap. Cycle-specific medians were compared against the pooled table and no material discontinuity was observed.
- Quantiles: Weighted empirical quantiles (P5, P25, P50, P75, P95) were computed for each sex × 5-year age bracket using linear interpolation on the weighted cumulative distribution. Survey-design standard errors were not computed.
This is an internally derived dataset, not a peer-reviewed publication. The derivation method and its limitations are summarised on the reference page.
Population and clinical context
The US adult population has one of the highest obesity rates among high-income countries (42.4% obese by BMI, Hales et al. 2020), so WHtR percentiles on this site sit higher than reference values from leaner populations. For cross-population context, a Colombian national survey found substantially lower WHtR at every age, with young Colombian men at a median of 0.47 versus 0.52 in this US dataset (Ramirez-Velez et al. 2016).
On clinical interpretation, the widely cited 0.5 threshold (waist less than half your height) was validated in a British meta-analysis that found WHtR above 0.5 identifies cardiometabolic risk missed by BMI alone (Ashwell et al. 2010). Because the 0.5 boundary sits at or below the 25th percentile in most US adult age groups in this dataset, percentile rank and clinical threshold tell different stories: a US adult at the population median is already above the 0.5 cut-off.