Objective: The dietary diversity score (DDS) is a good indicator of diet quality as well as of diet-disease relationships; therefore, the present study was undertaken to reveal the effect of a lifestyle intervention on this index.
Design: A baseline and three evaluation studies were conducted in two intervention districts (Isfahan and Najaf-Abad) and a reference area (Arak), all located in central Iran. The Isfahan Healthy Hearth Programme (IHHP) targeted the entire population of nearly 2 million in urban and rural areas of the intervention communities. One of the main strategies of the lifestyle intervention phase in the IHHP was healthy nutrition. Usual dietary intake was assessed using a forty-nine-item FFQ. A diversity score for each food group was calculated and the DDS was considered the sum of the diversity scores of the food groups.
Results: There were significant increases in DDS in both intervention areas (P = 0.0001) after controlling for confounding factors. There was a significant interaction between area and evaluation stage with regard to DDS (P = 0.0001). The effect of the intervention on the diversity scores of all food groups was also significant (P = 0.0001 for all) after adjusting for socio-economic status.
Conclusion: The community-based lifestyle intervention in the IHHP was successful in improving DDS which might be related to an increase of diet quality of the population that in turn might decrease the risks of chronic diseases.