Trends in dietary food groups and Dietary Approach to Stop Hypertension (DASH) score among adults: A longitudinal study from the Tehran Lipid and Glucose Study, 2006-2017.

OBJECTIVES: This study aimed to examine the secular trends of dietary food groups and diet quality among adults, overall and by sex, education, and employment status. METHODS: This study was conducted within the framework of the Tehran Lipid and Glucose Study. Demographic and anthropometric measurements were gathered using standard questionnaires. In terms of socioeconomic information, participants were divided into two groups according to their educational level and employment status. The regular dietary intakes of participants were gathered with a validated and reliable food frequency questionnaire over the previous year, and Dietary Approaches to Stop Hypertension scores were computed to evaluate diet quality. Generalized estimating equations were used to assess secular trends in food groups within the four phases. RESULTS: From 2006 to 2017, intake of whole grains, legumes, and nuts and seeds increased, and intake of refined grains, dairy products, and solid fats decreased significantly (P for trend < 0.001). Dietary fruit, vegetable, meat, and soft drink intake did not change significantly. According to socioeconomic groups, meat intake decreased significantly among men, uneducated, and unemployed participants, and fruit intake increased in both women and educated participants. Based on a 40-point scale, the Dietary Approaches to Stop Hypertension score increased from 18.1 ± 0.0 in phase1 to 22.7 ± 0.1 in phase 4 of the Tehran Lipid and Glucose Study (P for trend < 0.001). CONCLUSIONS: Over a decade, in addition to improvements in intake of a number of dietary food groups, the estimated overall diet quality of the study population showed a modest improvement. These findings may determine areas for more attention to improve the overall dietary intake of the population.