Stability of dietary patterns in young women over a 2-year period.

OBJECTIVE: To examine the stability of dietary patterns in young women over a two-year period and to identify factors that influence stability. DESIGN: A food frequency questionnaire was used to assess diet. In a subgroup, this was repeated after 2 years. Questions were asked about major changes to diet over this time. Dietary patterns were identified using principal components analysis and pattern scores were compared at the two time points. The consumption of foods was also examined. The relationship between change in pattern scores and socio-demographic factors and body mass index was assessed. SETTING: The Southampton Women's Survey, a prospective study of diet, health and lifestyle in young women and their influences on fetal growth. SUBJECTS: A subgroup of 94 women from a cohort of 6129 nonpregnant women aged 20-34 years. RESULTS: Two dietary patterns, labelled 'prudent' and 'high energy', were identified. Spearman correlation coefficients between the initial and repeat scores for the prudent and high-energy patterns were 0.81 and 0.64, respectively. Average changes (repeat - initial) were 0.13 and -0.01 SD of initial score. Change in prudent dietary pattern score was influenced by amount of strenuous exercise taken and by changes in partnership status. An increase in high-energy pattern score was associated with lower social class. CONCLUSIONS: Dietary patterns in young women are reasonably stable over a 2-year period. This suggests that dietary patterns identified in the recent past may provide useful information about current dietary patterns.

Dietary patterns in the Southampton Women's Survey.

OBJECTIVE: Dietary pattern analysis is receiving increasing attention as a means of summarizing the multidimensional nature of dietary data. This research aims to compare principal component analysis (PCA) and cluster analysis using dietary data collected from young women in the UK. DESIGN: Diet was assessed using a 100-item interviewer-administered food frequency questionnaire. PCA and cluster analysis were used to examine dietary patterns. SETTING: Southampton, UK. SUBJECTS: A total of 6125 non-pregnant women aged 20-34 years. RESULTS: PCA identified two important patterns: a 'prudent' diet and a 'high-energy' diet. Cluster analysis defined two clusters, a 'more healthy' and a 'less healthy' cluster. There was a strong association between the prudent diet score and the two clusters, such that the mean prudent diet score in the less healthy cluster was -0.73 standard deviations and in the more healthy cluster was +0.83 standard deviations; the difference in the high-energy diet score between the two clusters was considerably smaller. CONCLUSIONS: Both approaches revealed a similar dietary pattern. The continuous nature of the outcome of PCA was considered to be advantageous compared with the dichotomy identified using cluster analysis. SPONSORSHIP: The study was funded by the Dunhill Medical Trust, the University of Southampton and the Medical Research Council.

Impact of educational attainment on the quality of young women's diets.

OBJECTIVE: New findings, that relate poor foetal growth to long-term outcomes, highlight the need to understand more about the nature of women's diets before and during pregnancy. This study examines the influence of sociodemographic and anthropometric factors on the quality of the diets of young women in the UK. DESIGN: Diet was assessed by an interviewer-administered food frequency questionnaire. A single diet score was calculated for each woman using the first component defined by principal components analysis. SETTING: Southampton, UK. SUBJECTS: A total of 6125 non pregnant women aged 20-34 y. RESULTS: The diets of women with low diet scores were characterised by low intakes of fruit and vegetables, wholemeal bread, rice and pasta, yogurt, and breakfast cereals, but high intakes of chips and roast potatoes, sugar, white bread, red, and processed meat and full-fat dairy products. Educational attainment was the most important factor related to the diet score. In all, 55% (95% CI 50-59%) of women with no educational qualifications had scores in the lowest quarter of the distribution, compared with only 3% (95% CI 2-4%) of those who had a degree. Smoking, watching television, lack of strenuous exercise, and living with children were also associated with lower diet scores. After taking these factors into account, no other factor including social class, the deprivation score of the neighbourhood, or receipt of benefits added more than 1% to the variance in the diet score. CONCLUSIONS: Poor achievement at school defines a substantial group of women in the UK who may be vulnerable. Many of these women have poor diets that are not simply a result of the level of deprivation in their neighbourhood, or of living at a level of poverty that entitles them to benefits. We suggest that it is a priority to identify and to address the barriers that prevent these women from improving the quality of their diets. SPONSORSHIP: The study was funded by the Dunhill Medical Trust, the University of Southampton and the Medical Research Council.

What do babies eat? Evaluation of a food frequency questionnaire to assess the diets of infants aged 6 months.

OBJECTIVE: To evaluate the relative validity of a food frequency questionnaire (FFQ) for assessing nutrient intakes in 6-month-old infants. DESIGN AND SETTING: The FFQ was developed to assess the diets of infants born to women in the Southampton Women's Survey (SWS), a population-based survey of young women and their offspring. The energy and nutrient intakes obtained from an interviewer-administered FFQ were compared with those obtained from a 4-day weighed diary. SUBJECTS AND METHODS: A sub-sample of 50 infants aged 6 months from the SWS had their diets assessed by both methods. The FFQ recorded the frequencies and amounts of milks, baby foods, regular foods and drinks consumed by the infants over the previous seven days. The diaries recorded the weights of all foods and drinks consumed by the infants on four separate days within 15 days following FFQ completion. RESULTS: Spearman rank correlation coefficients for intakes of energy, macronutrients and 18 micronutrients, determined by the two methods, ranged from r = 0.39 to 0.86; adjustment for energy intake tended to increase the correlation coefficients, range r(a) = 0.55 to 0.89. Bland-Altman statistics showed that mean differences between methods were in the range of -12.5% to +12.5% except for vitamin B12 (-18.9%). CONCLUSION: Although there were differences in absolute energy and nutrient intakes between methods, Spearman rank correlation coefficients indicated reasonable agreement in the ranking of intakes. The interviewer-administered FFQ is a useful tool for assessing energy and nutrient intakes of healthy infants aged about 6 months.