Age-related changes in the social, psychological, and temporal influences on food intake in free-living, healthy, adult humans

Background. Elderly humans often have a reduction in intake that can produce malnutrition and impaired health. As a result, there is a need to investigate age-related changes in the eating behaviors of free-living humans. Methods. To address this issue, 7-day diet diary records that had been collected from 762 paid participants were reanalyzed, separating the participants into four age groups: 20-34 years, 35-49 years, 50-64 years, and 65 years and older. Results. The elderly ate with fewer other people present and earlier in the day than younger people. The elderly were found to be as responsive as younger groups to social facilitation of intake, palatability, cognitive restraint, time of day, day of week, and location, but showed blunted responses to self-reported hunger. Conclusions. There does not appear to be a decline with age in the ability of nonphysiological factors to influence the nutrient intakes of the elderly, but they may not have as great an influence due to lower absolute levels, This suggests that the deficient intakes in the elderly might be corrected or ameliorated by manipulation of nonphysiological factors, such as the number of other people present at meals, the palatability of meals, and the time of day and location of meals.