Background: Better diet quality has been linked to fewer physical limitations and slower rates of cognitive decline in older adults. Many studies have looked at individual components of dietary patterns rather than overall diet quality.
Objective: To assess diet quality using HEI-2015, physical limitations, and cognitive function in adults 60 years and older.
Methods: Dietary intake, physical functioning questionnaire (PFQ), and cognitive functioning questionnaire (CFQ) data from 2011-2014 National Health and Nutrition Examination Survey (NHANES) were analyzed. Participants (n=3,632) were stratified into 60-64 years, 65-74 years, and 75+ years. Dietary intakes were assessed using the Automated Multiple Pass Method to determine diet quality. PFQ assessed difficulty completing various physical tasks. CFQ assessed cognitive function based on Digit Symbol Substitution Test (DSST), Consortium to Establish a Registry for Alzheimer's Disease (CERAD) Word Recall, and Animal Fluency test scores.
Results: Adults who were 60-64 years old (HEI=53.1) had significantly poorer diet quality than adults 65-74 years old (HEI=55.8) and 75+ years (HEI=56.9, p=0.002). The most frequent limitations across all age groups were stooping, crouching, or kneeling, standing for long periods, and pushing or pulling large objects. Adults 75+ years (4.2) reported a significantly greater number of physical limitations than adults 60-64 years old (3.0) and 65-74 years old (2.9). The older participants had significantly poorer cognitive functioning scores, with significant differences between all age groups (p<0.001) for DSST, CERAD, and Animal Fluency test.
Conclusions: Adults 75+ years had better diet quality than the other age groups but reported more physical limitations and exhibited poorer cognitive test scores. Dietary intakes have been shown to be protective against physical and cognitive decline; therefore, better diet should be encouraged earlier in life. Future research is needed to assess the association between diet quality, physical function, and cognitive function in the aging population.