Convenience-based food purchase patterns: identification and associations with dietary quality, sociodemographic factors and attitudes.

OBJECTIVE: The present study aimed to derive food purchase patterns considering the convenience level of foods. Associations between identified patterns and dietary quality were analysed, as well as household characteristics associated with the dietary patterns. DESIGN: A Convenience Food Classification Scheme (CFCS) was developed. After classifying basic food groups into the CFCS, the formed groups were used to apply a factor analysis to identify convenience-based food purchase patterns. For these patterns nutrient and energy densities were examined. Using regression analysis, associations between the adherence to the patterns and household characteristic and attitude variables were analysed. SUBJECTS: The study used representative German food purchase data from 2011. Approximately 12 million purchases of 13 131 households were recorded in these data. RESULTS: Three convenience-based patterns were identified: a low-convenience, a semi-convenience and a ready-to-eat food pattern. Tighter adherence to the semi-convenience pattern was shown to result in the lowest nutrient and highest energy densities. Important factors influencing adherence to the patterns were household size, presence of children and attitudes. Working full-time was negatively associated with adherence to the low-convenience pattern and positively with the ready-to-eat pattern. CONCLUSIONS: Convenience foods were an important part of households' food baskets which in some cases led to lower nutritional quality. Therefore, it is important to offer convenience foods higher in nutrient density and lower in energy density. Interventions targeted on enhancing cooking skills could be an effective strategy to increase purchases of unprocessed foods, which, in turn, could also contribute to an improved diet quality.

Food purchase patterns: empirical identification and analysis of their association with diet quality, socio-economic factors, and attitudes.

BACKGROUND: Empirically derived food purchase patterns provide information about which combinations of foods were purchased from households. The objective of this study was to identify what kinds of patterns exist, which level of diet quality they represent and which factors are associated with the patterns. METHODS: The study made use of representative German consumption data in which approximately 12 million food purchases from 13,125 households are recorded. In accordance with healthy diet criteria the food purchases were assigned to 18 food groups of the German Food Pyramid. Based on these groups a factor analysis with a principal component technique was applied to identify food patterns. For these patterns nutrient and energy densities were examined. Using regression analysis, associations between pattern scores and socio-economic as well as attitude variables, reflecting personal statements about healthy eating, were analyzed. RESULTS: In total, three food purchase patterns could be identified: a natural, a processed and a traditional one. The first one was characterized by a higher purchasing of natural foods, the second by an increased purchasing of processed foods and the third by a meat-oriented diet. In each pattern there were specific diet quality criteria that could be improved whereas others were in line with actual dietary guidelines. In addition to socio-demographic factors, attitudes were significantly associated with the purchase patterns. CONCLUSIONS: The findings of this study are interesting from a public health perspective, as it can be assumed that measures focusing on specific aspects of diet quality are more promising than general ones. However, it is a major challenge to identify the population groups with their specific needs of improvement. As the patterns were associated with both socio-economic and attitude variables these grouping criteria could be used to define target groups.

Association between the Healthy Eating Index-2010 and nutrient and energy densities of German households' food purchases.

Background: The USDA Healthy Eating Index (HEI) is used widely to measure diet quality because it allows a number of different applications. Although several evaluations of the HEI-2010 have already been carried out, there is lack of those which focus on associations between the HEI and nutrient intakes. This study updates and expands upon previous findings on these associations. Using German consumption data, where ∼12 million purchases from 13 131 households are recorded, HEI-2010 total and individual scores, as well as several energy and nutrient densities were calculated. Correlations between the HEI and individual energy and nutrient densities were carried out to identify which nutrients are more or less well represented by the HEI. The HEI had the highest correlations with energy density and the densities of water-soluble vitamins (e.g. folic acid) and minerals (e.g. calcium). Weaker associations were identified for the densities of fat-soluble vitamins (e.g. vitamin D) as well as of the vitamins B1 and B12. Negligible correlations were detected for the densities of trace elements (e.g. fluoride and iodine), salt and fat composition. Given that energy intake and the intake of plant-based foods are relevant dietary issues, the HEI-2010 can be defined as a meaningful index to describe diet quality. However, because the intakes of salt, trace elements (e.g. fluoride and iodine) and fat-soluble vitamins, as well as the fat composition may be less reflected, they should be analyzed separately when using the HEI for measuring diet quality.