The NIH-AARP Diet and Health Study baseline questionnaire included a 124-item FFQ that was an early version of the Diet History Questionnaire (18). Participants were asked to report their usual frequency of intake and portion size over the preceding 12 months for each of the 124 food items plus provide responses to an additional 21 questions on intake of low-fat and high-fiber foods and on food preparation. Respondents indicated reported intake using 10 frequency categories ranging from ‘never’ to ‘6+ times per day’ for beverages and from ‘never’ to ‘2+ times per day’ for solid foods as well as 3 categories for portion size. Responses to frequency and portion size questions allowed for calculation of estimated daily energy intake based on national dietary data from the US Department of Agriculture’s 1994–96 Continuing Food Intake by Individuals (19). Additional details of the questionnaire design and its validity have been reported elsewhere (19–23).