Dietary patterns in pregnancy and associations with nutrient intakes.

Despite the recent popularity in the use of dietary patterns to investigate diet-disease associations, the associations between dietary patterns and nutrient intakes have not been fully explored. This paper determines the linear and non-linear associations between estimated nutrient intake (considered as both absolute and relative intake) and distinct dietary patterns, obtained during the third trimester of pregnancy using principal components analysis (PCA). It also examines the proportion of variability explained by the patterns in food and nutrient intakes. Pregnant women were asked to record the frequency of consumption of a variety of food items as part of regular self-completion questionnaires, the primary source of data collection in the Avon Longitudinal Study of Parents and Children, 12 035 cases were available. Individual dietary components were identified using PCA and scores on these components were related to estimated nutrient intakes. Five individual dietary patterns were established to best describe the types of diet being consumed in pregnancy. Scores on the 'processed' and 'confectionery' patterns were negatively related to the estimated intake of most nutrients with the exception of energy, fats and sugars, which increased with higher scores. Scores on the 'health-conscious' and 'traditional' components showed positive linear relationships with all nutrients. The results presented here suggest that dietary patterns adequately characterize dietary intake. There is, therefore, potential for dietary patterns to be used as a valid tool in assessing the relationship between diet and health outcomes, and dietary pattern scores could be used as covariates in specific nutrient-disease studies.