Population studies from around the world have shown that there are inequalities in the quality of young children’s diets, with children from more disadvantaged families tending to have the poorest-quality diets⁽ Reference Fisk, Crozier and Inskip ^{1 –} Reference Kranz and Siega-Riz ^{4 )}. Establishing a good-quality diet in early life is important for optimal growth and development as well as for long-term health. A good-quality diet is typically characterised by high intakes of unprocessed, micronutrient-dense foods (e.g. fruit, vegetables and whole-grains), and conversely a poor-quality diet is typically characterised by high intakes of highly processed foods and foods high in fat, salt or sugar (e.g. potato chips, white bread and soft drinks)⁽ Reference Fisk, Crozier and Inskip ^{1 )}.

To intervene to influence the quality of young children’s diets requires an understanding of the determinants of food choice at this age. The association between children’s quality of diet and socio-economic factors is well established⁽ Reference Fisk, Crozier and Inskip ^{1 –} Reference Kranz and Siega-Riz ^{4 )}, but in addition influences within the child’s immediate environment and a number of maternal, child, mealtime and home environmental characteristics appear to be important. The home food environment has been studied extensively with no consistent definitions of the concept. Rosencranz and Dzewaltowski addressed this by developing a comprehensive framework of the factors included in the home food environment⁽ Reference Rosenkranz and Dzewaltowski ^{5 )}. They showed that home food environment is a global term which could include many factors. Our study focused on the child’s physical mealtime environment, which Rosencranz and Dzewaltowski describe as ‘family eating patterns’. This includes whether children are sat at a table or in front of the television to eat their meals and how often meals consist of takeaway foods. In addition, household food security is an important factor in the model of the home food environment. All of these factors have been shown to be associated with pre-school children’s quality of diet. For example, children who consume meals while sitting at the table and with other family members present are more likely to have better-quality diets⁽ Reference Wyse, Campbell and Nathan ^{6 ,} Reference Campbell, Crawford and Ball ^{7 )}, whereas children who eat their meals in front of the television and who live in a food-insecure household have been shown to have diets of poorer quality⁽ Reference Pilgrim, Barker and Jackson ^{8 ,} Reference Fitzpatrick, Edmunds and Dennison ^{9 )}. Moreover, maternal factors such as educational attainment⁽ Reference North and Emmett ^{2 )} and the way in which a mother exercises control over her child’s diet⁽ Reference Brown, Ogden and Vogele ^{10 )} have also been identified as influences on children’s diet quality. These factors are often interrelated, however, and there have been some studies that have considered multiple characteristics of the mother and home/mealtime environment and how, in combination, they influence the quality of young children’s diets.

One such study assessed how aspects of the home mealtime environment and parental feeding practices influenced pre-school children’s dietary patterns. It reported that children who were allowed to consume meals in front of the television, did not eat in the company of their parents and were in households which purchased more takeaway foods were more likely to have a poorer quality of diet. In addition, children whose parents used food as a reward and who did not restrict access to foods were also likely to have poorer-quality diets⁽ Reference Spurrier, Magarey and Golley ^{11 )}. A more recent, comprehensive study that considered the interplay between some parental and home environmental factors suggested that parents cluster into groups according to aspects of their diet-related parenting practices (e.g. whether parents have rules about, or model, fruit, snack and sugar-sweetened beverage intake) and their food environment such as availability, accessibility and visibility of more and less healthy foods⁽ Reference Rodenburg, Oenema and Kremers ^{12 )}. These clusters were associated with children’s fruit, snack and sugar-sweetened beverage intake. For example, parents in the ‘high visibility and accessibility of unhealthy foods’ cluster were likely to have children who consumed more unhealthy and fewer healthier foods, while the reverse was seen in children whose parents were in the ‘low availability of unhealthy foods’ cluster⁽ Reference Rodenburg, Oenema and Kremers ^{12 )}. That study implied that some maternal characteristics, the home and mealtime environments and parental feeding practices may work in combination to determine children’s quality of diet.

To date there has been little consideration of the role of individual psychological characteristics of parents and how they shape the home food environment of young children or their quality of diet. Maternal psychological factors are known to be important determinants of the food choices a woman makes for herself. Bandura’s social cognitive theory of the socio-environment and personal determinants of health behaviours holds self-efficacy as a central construct. Self-efficacy describes an individual’s belief in his/her ability to carry out a behaviour and has been shown to be an important predictor of women’s quality of diet⁽ Reference Lawrence, Schlotz and Crozier ^{13 )}. In addition, factors such as perceived control over life, food involvement (which indicates the importance someone places on food) and well-being⁽ Reference Barker, Lawrence and Woadden ^{14 ,} Reference Jarman, Lawrence and Ntani ^{15 )} have been shown to be associated with quality of diet in women, which in turn is known to be an important influence over the way that they feed their children⁽ Reference Cooke, Wardle and Gibson ^{16 –} Reference Fisher, Mitchell and Smiciklas-Wright ^{18 )}. These psychological factors are also known to be highly correlated with one another. Perceptions of control in some senses overlap with self-efficacy⁽ Reference Ajzen ^{19 )} and self-efficacy underlies a sense of well-being⁽ Reference Bandura ^{20 )}. A small number of studies have considered individual maternal psychological factors in relation to child diet. One such study has shown a direct association between mother’s level of food involvement and child’s quality of diet, demonstrating that mothers with lower levels of food involvement have children who consume fewer fruits and vegetables⁽ Reference Ohly, Pealing and Hayter ^{21 )}. Another study reported that mothers with higher levels of negative affect (lower well-being) tended to feed their children a diet higher in low-micronutrient, energy-dense foods such as chips, cakes and sugar-sweetened soft drinks⁽ Reference Ystrom, Barker and Vollrath ^{22 )}.

To date, however, there has been little exploration of the interrelationship between maternal psychological characteristics, young children’s mealtime environment and their combined impact on young children’s quality of diet. Based on the known relationships between maternal psychological characteristics and food choice in women, it is hypothesised that mothers who feel more in control of life and have higher levels of self-efficacy, well-being and food involvement will manage their children’s mealtime environments more favourably and have children with better quality of diet.

Methods

Participants

Participants were a sub-sample of women enrolled in a larger study, the Southampton Initiative for Health (SIH)⁽ Reference Barker, Baird and Lawrence ^{23 )}, who had a child aged between 2 and 5 years old. The SIH was a community-based intervention study that aimed to improve the diets and lifestyles of women of childbearing age. The present sub-study aimed to examine the relationship between nutrition behaviours in mothers and their young children.

Procedure

Between January and July 2009, 1022 women attending Sure Start Children’s Centres in Southampton, Gosport and Havant, towns on the south coast of the UK, were recruited to the SIH study, representing 96 % of those who were approached. Women were asked if they would be willing to provide information about their own diet and health-related behaviours, and 973 women who completed the baseline study agreed to be contacted again. Details of the procedures used in the SIH have been published elsewhere⁽ Reference Barker, Baird and Lawrence ^{23 )}. Of these 973 women, 572 (59 %) had a child between the ages of 2 and 5 years and were contacted again via telephone between December 2009 and May 2010 and invited to take part in the sub-study. Over 60 % (n 348) of mothers agreed to take part and completed the sub-study. If the mother had two eligible children, she was asked about the younger child. Information was collected during telephone interviews by trained fieldworkers who adhered to a strict study protocol. At the beginning of the telephone call, the interviewer read out a participant information sheet and answered any questions that arose. Verbal consent to take part in the study was obtained over the telephone. The study was conducted according to the guidelines laid down in the Declaration of Helsinki and all procedures involving human participants were approved by the University of Southampton School of Medicine ethics committee.

Materials

The validated scales included in the questionnaires to assess general and specific self-efficacy, perceived control, food involvement, well-being, overt and covert control, food security and screen time are detailed in Table 1.

Table 1 Assessments used in the maternal and child questionnaires

* Cronbach’s α is an assessment of internal validity in scales; a score of above 0·6 is generally considered to represent good internal validity.

Development of the FFQ

A short FFQ was developed for the current study based on data collected from 1640 children aged 3 years who were part of the Southampton Women’s Survey (SWS), a birth cohort study. Diets of children in the SWS were assessed using an interviewer administered eighty-item FFQ⁽ Reference Fisk, Crozier and Inskip ^{1 )}. In a principal component analysis, the primary dietary pattern among these children was characterised by frequent consumption of fruit, vegetables and wholemeal bread and infrequent consumption of potato chips, crisps, sweets and soft drinks. This pattern was labelled ‘prudent’. A prudent dietary pattern score was calculated for each child using the component coefficients and reported frequencies of consumption. Prudent diet scores indicate compliance with the prudent pattern and were used as an indicator of the children’s diet quality⁽ Reference Fisk, Crozier and Inskip ^{1 )}. We have previously shown that a short FFQ that includes the twenty foods that characterise the prudent dietary pattern can be used to assess this dietary pattern in young women and that prudent pattern scores for short and long FFQ are highly correlated⁽ Reference Crozier, Inskip and Barker ^{24 )}. Furthermore, comparable positive associations between prudent diet scores defined using the short and long FFQ were found with a blood biomarker (red cell folate). In the present study, the twenty foods that had the greatest influence on the prudent diet pattern at 3 years in the SWS were used to construct a short FFQ to assess diet quality in young children. To evaluate the ability of the short, twenty-item FFQ used in the present study to rank children according to their compliance with the prudent diet pattern, a pilot study was carried out in which the diets of forty-five pre-school children were assessed using both the long eighty-item FFQ and the shorter twenty-item FFQ. The assessments were separated by between 12 and 20 weeks. Prudent diet scores from the full and short FFQ were found to be highly correlated (r=0·68, P=<0·001).

Assessment of children’s diet quality

Children’s quality of diet was assessed using the short FFQ administered to the mother, to report how often in the last three months her child had consumed twenty food and drink items. Responses were ‘never’, ‘less than once per month’, ‘1–3 times per month’, ‘between 1–7 times per week’ or ‘more than once per day’. If any food or drink items were consumed more than once per day then the number of times was recorded. A prudent diet score was calculated for each child by taking the sum of the coefficients from principal component analysis multiplied by the reported frequency of consumption for each of the twenty food items. Scores were standardised and expressed at Z-scores such that they have a mean of 0 and a standard deviation of 1.

Home and mealtime environment

The mealtime environment was assessed using tools developed in previous studies. Mothers were asked how often in the last three months her child had: ‘eaten an evening meal with the family?’ and ‘eaten meals whilst the television was on?’⁽ Reference Wyse, Campbell and Nathan ^{6 )}, ‘eaten takeaway foods, including fish and chips?’⁽ Reference MacFarlane, Cleland and Crawford ^{25 )} and ‘eaten whilst sat at a table?’⁽ Reference Fitzpatrick, Edmunds and Dennison ^{9 )} The responses were ‘never’, ‘less than once per month’, ‘once every two weeks’, ‘1–2 times per week’, ‘3–6 times per week’, ‘once per day’ and ‘more than once per day’. Responses were coded from 0 to 6.

Information on mother’s diet, educational attainment, employment, age, number of children and clothing size was also collected. A UK clothing size of 16 or smaller is associated with lower odds of developing cardiovascular risk factors such as hypertension or type 2 diabetes⁽ Reference Han, Gates and Truscott ^{26 )}.

Statistical analysis

Statistical analysis was carried out using the statistical software package Stata version 12. A Spearman rank correlation matrix was used to assess the relationships between the maternal psychological variables and children’s quality of diet. Cluster analysis was performed on the psychological variables (general control, well-being, general self-efficacy, self-efficacy for healthy eating and food involvement) using Ward’s linkage to generate initial clusters. The resulting dendrogram from this hierarchical procedure was used to determine the number of clusters. Following this k-means analysis based on squared Eucilidean distances was used as a further iterative process, as recommended by Milligan and Cooper⁽ Reference Milligan and Cooper ^{27 )}. Child’s median weekly food consumption according to mother’s cluster membership was assessed using the median test for difference. Differences in characteristics according to cluster membership were assessed using χ ² statistics for categorical data and t tests for parametric continuous variables. Univariate and multivariate linear regression models were used to assess the relationships between cluster membership and children’s quality of diet.

Results

Characteristics of mothers and children

Complete data were available on 324 mothers and children. Table 2 describes the child, maternal and home/mealtime characteristics of the 324 mother–child pairs. Due to small numbers some categories were collapsed in the variables food security and mealtime environment. Families in the present study came from a range of backgrounds; 38 % of mothers had a low educational attainment (General Certificate of Secondary Education or lower) and 17 % of the households were classed as food insecure/hungry. The majority (85 %) of mothers reported wearing clothes which were UK size 16 (European size 44, American size 12) or smaller.

Table 2 Characteristics of the 324 mother–child pairs studied, Southampton Initiative for Health, UK, December 2009–May 2010

IQR, interquartile range; GCSE, General Certificate of Secondary Education.

* UK size 16 is equivalent to European size 44 or American size 12.

Cluster analysis

The dendrogram resulting from the cluster analysis is shown in the online supplementary material, Supplemental Fig. 1; from this two distinct clusters were identified. Mothers in cluster 1 tended to have higher scores for all of the psychological variables compared with those in cluster 2 (all P≤0·001, data not shown) showing that mothers in cluster 1 tend to have higher levels of self-efficacy, perceived control, well-being and food involvement. Figure 1 displays the percentage of mothers in each cluster with scores on the psychological assessments above the median. There are clear differences between mothers in each cluster. For example, 79 % of mothers in cluster 1 had a well-being score above the median compared with only 7 % of those in cluster 2. Therefore cluster 1 was termed ‘more resilient’ and cluster 2 was termed ‘less resilient’. Resilience is a psychological concept from personality theory and refers to a person’s ability to respond and adapt effectively to challenges and adversity⁽ Reference Block and Kremen ^{28 )}.

Fig. 1 The percentage of women with scores above the median for psychological factors according to cluster membership (, cluster 1, ‘more resilient’; , cluster 2, ‘less resilient’) among mothers of pre-school children (n 324) in the Southampton Initiative for Health, UK, December 2009–May 2010. *Difference in proportion is significant, P≤0.001

Differences in maternal and home/mealtime characteristics according to mother’s cluster membership were explored. Mothers who were in the less resilient cluster tended to be of lower educational attainment (P≤0·001) and to have more children (P=0·03); in addition they were more likely to live in a food-insecure household (P≤0·001). In terms of how they shaped their children’s eating environment, mothers in the less resilient cluster were less likely to use a covert style of feeding practice to control their children’s diet (P=0·002) and their children ate meals while sitting at a table less often (P=0·03) and were more likely to consume takeaway foods (P=0·05). Their children were also more likely to spend more hours in front of a screen (P=0·01).

Association with child’s quality of diet

Children of mothers in the less resilient cluster tended to consume fewer weekly portions of fruit and vegetables, less water and more crisps, confectionery, white bread and low-calorie soft drinks (all differences P≤0·05) than children with mothers in the more resilient cluster.

A univariate analysis showed that children of mothers in the less resilient cluster tended to have a poorer-quality diet than those with mothers in the more resilient cluster. Being in the less resilient cluster was associated with a reduction in child’s diet quality score of 0·61 sd (95 % CI −0·82, −0·40, P≤0·001). The association between cluster membership and child’s prudent diet score is displayed in Fig. 2. The association was attenuated but remained significant even after controlling for the maternal and mealtime environmental factors. The adjusted model is displayed in Table 3. This shows that, even after taking account of the effects of mealtime characteristics and maternal education, being a child of a mother in the less resilient cluster was associated with a reduction in diet quality score of 0·29 sd.

Fig. 2 Bar graph showing pre-school children’s mean prudent diet score (Fisher–Yates Z-score) according to mothers’ cluster membership (cluster 1, ‘more resilient’; cluster 2, ‘less resilient’) among mother–child pairs (n 324) in the Southampton Initiative for Health, UK, December 2009–May 2010. Values are means with their 95 % confidence intervals represented by vertical bars

Table 3 Mutually adjusted multivariate linear regression model showing the independent associations of cluster membership, maternal characteristics and mealtime environmental characteristics with pre-school children’s prudent diet score among mother–child pairs (n 324) in the Southampton Initiative for Health, UK, December 2009–May 2010

Regression model is adjusted for all variables in the table as well as number of children and mother’s age at interview.