Skip to Main Content

An official website of the United States government

Four instruments collect dietary data.


The Diet History Questionnaire (DHQ II) is an online food frequency questionnaire (FFQ) that asks about a list of food eaten in the past 12 months. The frequency and quantity of these foods were recorded.

The food frequency files contain one record per food, with the two administrations split into different datasets. The nutrient file contains one record per person with an array of the two administrations. The raw questionnaire contains one record per person per administration with their responses to the questionnaire.

Click here for data dictionaries and formats for the DHQ files. Datasets can be obtained by submitting a request.

Summary Available Data
  • Self-reported data collected via a web-based FFQ
  • Completed the first and last month of the study, about 1 year apart
  • ~1,010 participants with results
    • ~710 completed both administrations
    • ~205 completed only the 1st
    • ~90 completed only the 2nd
  • Date and time
  • Demographics
  • Carbohydrate Constituents
  • Vitamins
  • Minerals
  • Carotenoids and Tocopherols
  • Other
  • Macronutrients and Energy
  • Fats, Fatty Acids and Cholesterol
  • Protein Constituents
  • My Pyramid Equivalents
  • Food Pyramid Equivalents