NHANES — National Health and Nutrition Examination Survey

Overview

NHANES combines household interviews with standardized physical examinations conducted in mobile examination centers. This U.S. nationally representative survey can be used to generate national estimates of health conditions, nutrition status, environmental exposures, and oral health indicators.

Population: U.S. civilian, non-institutionalized | Years: 1999–present

Design: Complex, stratified, multistage probability sample

Participants per year: ~5,000

Data types: Interview, exam, laboratory, dietary, dental

Access: Public-use files + restricted files via application

Steps for Data Access

  1. Identify survey cycle(s) and components needed.
  2. Review documentation including analytic guidance and codebooks.
  3. Download public-use data files.
  4. Apply for restricted data if required.
  5. Incorporate sampling weights and design variables in analysis.

Visit the NHANES website

Age Distribution

Pie chart showing the age distribution of the NHANES sample across six groups. Adults aged 20–39 represent the largest share at 27.2%, followed by 40–59 at 25.5%, 60 and older at 22.5%, 12–19 at 10.7%, 6–11 at 7.9%, and 1–5 at 6.3%.

Sex Distribution

Pie chart showing the sex distribution of the NHANES sample. Female participants make up 51.1% and Male participants make up 48.9%, a near-equal split.

Racial and Ethnic Distribution 

Pie chart showing the racial and ethnic distribution of the NHANES sample. Non-Hispanic White is the largest group at 59.8%, followed by Non-Hispanic Black at 11.9%, Mexican American at 10.1%, Other Hispanic at 7.9%, Non-Hispanic Asian at 5.7%, and Other/Multiracial at 4.6%.