CCOI

CENTER FOR CLINICAL OBSERVATIONAL INVESTIGATIONS

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National Health and Nutrition Examination Survey (NHANES)

Organization: Centers for Disease Control and Prevention, National Center for Health Statistics

Image provided courtesy of NHANES

Description

The National Health and Nutrition Examination Survey (NHANES) collects data about the health of adults and children in the United States. It also collects data about what participants eat, drink, and take as supplements to determine how many nutrients are in their diet. These dietary interviews and blood tests help us measure the nutritional status of U.S. adults and children.

CDC's National Center for Health Statistics (NCHS) conducts NHANES, which is the only national health survey that includes health exams, laboratory tests, and dietary interviews for participants of all ages.

NHANES data can help improve the health of Americans. Survey data have driven changes in how doctors treat patients and how public policy supports good health.

Key Information

Dataset Contents
Data Date Span	August 2021 - August 2023
Patient Count	11,933
Deceased Count	N/A
Update Status	Closed
Dataset Type	Survey
Context	Self-reported survey data about health, diet, personal, social, and economic characteristics; laboratory tests; dental exams; health and body measurements
Region	United States
Age Restrictions	N/A

Dataset Contents

Data Date Span

August 2021 - August 2023

Patient Count

11,933

Deceased Count

N/A

Update Status

Closed

Dataset Type

Survey

Context

Self-reported survey data about health, diet, personal, social, and economic characteristics; laboratory tests; dental exams; health and body measurements

Region

United States

Age Restrictions

N/A

Access & Availability
Native Data Structure	Survey (includes weights to produce national estimates)
Hosting	Data downloadable from source
Database File Size	N/A
Availability Restrictions	None
Public Use Files	De-identified
Limited Access	De-identified

Access & Availability

Native Data Structure

Survey (includes weights to produce national estimates)

Hosting

Data downloadable from source

Database File Size

N/A

Availability Restrictions

None

Data Identifiability

Public Use Files

De-identified

Limited Access

De-identified

References and Resources:

Homepage: https://www.cdc.gov/nchs/nhanes/
Dataset Ethics Information: https://www.cdc.gov/nchs/nhanes/about/erb.html
Dataset Support Contact*: Contact CDC-INFO or by phone at 1 (800) 232-4636, TTY: 1 (888) 232-6348
NHANES linked datasets: NCHS Linked Data Table

Note: NHANES restricted data files are available through the NCHS Research Data Center (RDC) for a fee. To access restricted NHANES data, researchers must submit requests in the Standard Application Process portal. The RDC provides instructions for preparing and submitting an application to access restricted data.

Dataset Dictionary

Relevant Publications

A list of publications using NHANES can be found here: https://www.cdc.gov/nchs/nhanes/about-data/index.html

Last updated Apr 15, 2026