Development of a food frequency questionnaire (FFQ) for an elderly population based on a population survey

Older people have different eating patterns than their younger counterparts, although in most nutritional studies of older populations, food frequency questionnaires (FFQ) that were developed and validated for the general adult population are used. In this paper, we present the advantages of developing an FFQ for an older population based on a population survey. A random sample of the Negev's (Southern Israel) Jewish population greater than or equal to 35 y old was recruited and interviewed for their dietary intake using 24-h recalls. Foods eaten were aggregated into conceptually similar groups and entered into stepwise regression models to predict variation in nutrient intake. We interviewed 796 people age 35-64 y and 377 people greater than or equal to 65 y old for the study. Significantly more items were required to reach 80% between-person variability for zinc, magnesium, vitamin E and protein for the elderly compared with the younger age group. Portion sizes of most items consumed by the elderly were smaller compared with the Israeli Ministry of Health portion sizes booklet and the younger age group's intake estimates. The nutrient values assigned for each line based on a weighted mean of the intake of the elderly were different from those using the most frequently used item. The above findings highlight some of the advantages of developing an FFQ for an older population based on a population survey. Further studies are required to compare the validity of existing tools adapted for the elderly to those developed on the basis of population surveys.