Quality of food eaten in English primary schools: school dinners vs packed lunches

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1 (2007) 61, & 2007 Nature Publishing Group All rights reserved /07 $ ORIGINAL ARTICLE Quality of food eaten in English primary schools: school dinners vs packed lunches IS Rogers 1, AR Ness 1, K Hebditch 1, LR Jones 1 and PM Emmett 1 1 Avon Longitudinal Study of Parents and Children, Department of Social Medicine, University of Bristol, Bristol, UK Objective: To compare the food and nutrient intakes of primary school children eating school dinners and packed lunches. Subjects: Six-hundred and twenty-one 7-year-old children participating in the Avon Longitudinal Study of Parents and Children in South West England. Methods: Diet was assessed by 3-day unweighed food record. Results: The composition of both types of school meals compared unfavourably with dietary guidelines. Intakes of energy, nonstarch polysaccharides (NSP), calcium, iron, folate, retinol equivalents, zinc, copper, magnesium, iodine and riboflavin were too low, and intakes of total and saturated fat were too high. However, children who ate school dinners had higher lunchtime intakes of protein, starch, NSP and most vitamins and minerals and lower intakes of sugar (14.2 and 20.9% of energy in school dinners and packed lunches, respectively, Po0.001) and saturated fat (12.0 and 16.2%, Po0.001). Only around half of the recommended amount of fruit and vegetables was eaten by children having either type of school meal. There were also differences in the whole day s nutrient intake according to school meal type. Children eating packed lunches had lower daily intakes of potassium and zinc, and higher intakes of sugar and saturated fat. Differences in nutrient intake were independent of maternal education. Conclusions: The food and nutrient content of both school dinners and packed lunches needed improvement. However, the standard of food brought from home by children was, if anything, worse than that served at school. Recent moves to improve school dinners will need to be complemented by education about what constitutes a healthy packed lunch. Sponsorship: University of Bristol. (2007) 61, ; doi: /sj.ejcn ; published online 10 January 2007 Keywords: ALSPAC; children; school dinners; packed lunches; nutrition; healthy eating guidelines Introduction As a result of a recent British television series starring popular celebrity chef Jamie Oliver, there has been much debate, both public and political, over the standard of school dinners. Well-balanced school dinners could potentially reduce welldocumented inequalities in diet (Department for Environment, Food and Rural Affairs, 2001), being an important source of nutrients and other dietary constituents particularly Correspondence: Dr PM Emmett, Unit of Paediatric and Perinatal Epidemiology, University of Bristol, 24 Tyndall Avenue, Bristol BS8 1TQ, UK. P.M.Emmett@bristol.ac.uk Guarantor: IS Rogers. Contributor: All authors contributed to the design of the study and the interpretation of the data. PME, ISR and LRJ initiated and supervised the collection and preparation of the data. ISR and KH analysed the data. All authors contributed to the drafting and revision of the article. Received 14 October 2005; revised 26 July 2006; accepted 4 August 2006; published online 10 January 2007 for children entitled to free school meals (Gregory and Lowe, 2000). Statutory food-based guidelines for school dinners were introduced in 2001 (Department of Education and Employment, 2001). These specified that children should be offered at least one item from the following food groups daily: starchy foods (bread, potatoes, rice); fruit; vegetables; milk or dairy item; meat, fish or alternative source of protein. The effect of these guidelines has not yet been fully assessed, and the recent UK government pledges of more investment into school dinners are only just taking effect. Currently, the government does not have nutrient-based guidelines for school meals, although a set has been developed by the Caroline Walker Trust (CWT) (Crawley, 2005), and pressure is mounting for their adoption in addition to the food-based guidelines. These give recommended energy intakes, maximum desirable levels of fat, saturated fat, non-milk extrinsic/added sugars, and minimum levels of protein, non-starch polysaccharides (NSP, i.e. dietary fibre) and several vitamins and minerals. However, a

2 recent report on meals eaten in secondary schools in England found that only 7% of schools provided set meals over the course of 1 week that met eight or more of the CWT guidelines (Nelson et al, 2004). Given the negative publicity about the standards of school dinners, parents may believe that providing a packed lunch is a healthier alternative. The UK Food Standards Agency (FSA) recommends that packed lunches meet the nutritional standards described above for school dinners, and has many suggestions for packed lunch contents on its website ( The actual contents of packed lunches have been under less scrutiny than those of school dinners, but a recent survey of 9 11-year olds suggests that packed lunches rarely conform to these guidelines (Jefferson and Cowbrough, 2004). However, whereas both school dinners (Gregory and Lowe, 2000) and packed lunches (Jefferson and Cowbrough, 2004) have been found to perform badly in relation to recommendations, there is only one study comparing the two as eaten in similar groups of children. This was carried out in secondary schools and showed that eating school dinners was associated with more favourable levels of some chronic disease risk factors (Whincup et al, 2005). Social patterning of diet is likely to account partly for any differences in overall nutrient intake between children, but social position has seldom been accounted for in the available studies. There is also a lack of data on lunchtime nutrient intake by younger children. In this study, we used dietary records from British sevenyear-old to compare school dinners and packed lunches as consumed, and to assess how meals consumed at school, before the latest improved recommendations, compare to guidelines for food and nutrient intake. Methods Subjects The subjects were part of the Avon Longitudinal Study of Parents and Children (ALSPAC), a prospective study of pregnancies recruited from all pregnancies in the three Bristol-based District Health Authorities, with expected delivery between April 1991 and December The aims and study design have been described in more detail elsewhere (Golding et al, 2001, The children in this analysis were from a more intensively studied 10% subcohort of ALSPAC, randomly selected from those born in the last 6 months of the survey period the Children in Focus (CIF) group. These CIF children had dietary information available at age 7 years (Glynn et al, 2005). Ethical approval was obtained from the local research ethics committees covering the study area and from ALSPAC s Ethics Committee. Clinic assessment Between July 1999 and October 2000, the CIF children attended a research clinic at 7 years of age, where diet was assessed and they were weighed and measured. Height was measured to the last completed millimetre using a Harpenden stadiometer as described by Cameron (Cameron, 1986). Weight was measured to the nearest 50 g using a Tanita weighing scale (Tanita UK Limited, Uxbridge, UK). Body mass index (BMI) was calculated from weight (kg)/height (m) 2. Dietary assessment Diet was assessed using a 3-day unweighed dietary record. The dietary diaries were sent to the carer of the child in advance of the clinic. The carer was asked to complete the diaries by recording, in household measures, everything that the child ate and drank for two weekdays and one weekend day, and to bring the completed diaries with them to the clinic where they were checked for clarity and completeness. Portion size information for school dinners was obtained from catering services. The diaries were coded using the computer program DIDO (Diet In, Data Out), which is designed for direct entry of dietary records (Price et al, 1995). This was used in conjunction with an in-house nutrient database to generate food and nutrient intakes for each child. This has been described in detail elsewhere (Glynn et al, 2005). The nutrient and food group information obtained by this method compared well with that obtained by the British National Diet and Nutrition Survey of similar aged children using 7-day weighed records of food intake (Gregory and Lowe, 2000). On the front of each diary, the child s carer was asked to note if the recorded day was a school day, and whether the mid-day meal was a school dinner or packed lunch. Only school days were included in the current analyses. In the 3 days of dietary recording, most children should have eaten two meals at school; however, a number of carers (n ¼ 113) had filled in three school-day diaries for the child. The children were divided into two groups according to whether they ate school dinners or packed lunches. Mean dietary intakes from the meals were compared with guideline nutrient intakes for school meals taken from the CWT recommendations (Crawley, 2005), where available, or from the Reference Nutrient Intake (RNI) for the whole day s intake divided by three on the assumption that lunch should provide a third of the day s nutrient requirements. The RNI is a figure that should be sufficient to supply the needs of nearly all individuals (Department of Health, 1991). Sodium intake was compared with the recommendations of the Scientific Advisory Committee on Nutrition (SACN, 2003). Confounding variables Maternal educational level (highest obtained) was considered as a possible confounding variable, as this has been shown to be associated with dietary quality in this cohort. For example, increasing education level was associated with increasing fruit intake (North and Emmett, 2000; Rogers 857

3 858 et al, 2003), and was also associated with frequency of school meal consumption in the whole cohort (unpublished data). This was assessed by a questionnaire sent to the mother at 32 weeks gestation and grouped as follows: CSE or no qualifications, vocational qualifications, O level or equivalent, A level or equivalent, degree. CSE and O Level were, respectively, lower and higher levels of qualifications taken at around 16 years of age, A Levels were the standard qualifications taken at around 18 years of age. Statistical methods All statistical analyses were carried out using SPSS for windows version The level of significance used was Po0.05. Nutrient intakes with skewed distributions were transformed to the natural logarithm or square root before statistical analysis (the transformations used are indicated in the relevant tables). The differences in nutrient intakes, between children eating school dinners and those eating packed lunches were investigated initially using unpaired t-tests. We also tested to see whether any differences in nutrient intakes between the children eating the two types of school meals, persisted on adjustment for maternal educational level using two-way analysis of variance. The primary outcome investigated was nutrient intake per unit of energy (MJ), or nutrient density, at lunchtime, as nutrient densities canbeseenasameasureofthequalityornutrient richness of the diet. We also investigated how school meal consumption related to absolute nutrient intake at lunchtime so as to compare this to the dietary recommendations, most of which are in terms of absolute nutrient intakes. Finally, we examined the association with nutrient density of the whole day s diet to investigate whether any differences in lunchtime nutrient intake were counterbalanced by intakes at other meals. Analyses of nutrient densities were performed on both sexes combined. To take account of the differing energy intakes of boys and girls, analyses of absolute nutrient intakes were adjusted for sex. The types and amounts of food/drinks taken at the meals are presented separately for boys and girls to aid the formulation of practical advice tailored to the child. The proportion of children including each/all of the recommended food items in their packed lunches was investigated. The new recommendations rendered it unproductive to investigate school dinners in this way. analyses. Boys who were included were slightly younger (mean age ¼ 7.47 vs 7.53 years, Po0.001), shorter (mean height vs cm, P ¼ 0.014), lighter (geometric mean weight ¼ vs kg, P ¼ 0.006) and thinner (geometric mean BMI ¼ vs kgm 2, P ¼ 0.025) compared with the rest of the CIF cohort attending the clinic. Girls included were slightly younger (7.47 vs 7.51 years, Po0.001), but there was no difference in height, weight or BMI between girls included in the analysis and those, not. Compared to the rest of the CIF cohort who attended the clinic, those included in the analyses were more likely to have a more educated mother (48.1 vs 39.8% with the highest qualification A Level or degree, P ¼ 0.013). Nutrient density of food consumed at lunchtime Table 2 shows the nutrient density and energy content of the meals consumed at lunchtime in the two school meal groups. There were differences between the groups in the majority of nutrients investigated. Mean intakes of protein, starch and NSP were higher in those eating school dinners compared to those eating packed lunches, whereas intakes of energy, sugar and total carbohydrate were lower. There was no difference in the proportion of energy from fat in the different meal groups, but those children eating school dinners derived less energy from saturated fatty acids (SFA) more from polyunsaturated fatty acids (PUFA), and had lower intakes of trans-fatty acids (TFA). Mean intakes of potassium, magnesium, phosphorus, iron, zinc and iodine were higher among children eating school dinners, although selenium intake was lower. Mean intakes of most vitamins were higher among children eating school dinners, although there was no difference in riboflavin or vitamin C, and intakes of retinol and vitamin E were lower. Adjusting for maternal educational level had very little effect on the relationships observed. Absolute nutrient intakes at lunchtime Table 3 shows absolute nutrient intakes at lunchtime according to school meal type. Many of the differences observed for nutrient densities were present in the analysis of absolute nutrient intakes. Children who consumed school dinners had higher mean intakes of protein, NSP, potassium, Results Of 978 members of the CIF cohort attending the clinic (68% of 1432 invited), diet data were available for 814 children. Six hundred and seventy nine of these provided information on lunches eaten at school 410 recorded eating only packed lunches, 211 recorded eating only school dinners and 58 recorded eating a mixture of school dinners and packed lunches and were excluded from further analyses. Table 1 shows some characteristics of children included in the Table 1 Characteristics of children included in the study figures shown are mean (s.d.) Mean (s.d.) Boys (n ¼ 346) Girls (n ¼ 275) Age (year) 7.47 (0.10) 7.47 (0.10) Height (m) (0.050) (0.056) Weight (kg) (4.14) (4.76) BMI (kg m 2 ) (1.80) (2.16) Abbreviations: BMI, body mass index; s.d., standard deviation.

4 Table 2 Energy intake and nutrient densities (mean (s.d.) or geometric mean (95% CI)) either as percentage of energy (%E) or per unit of energy (MJ) at lunchtime, according to type of meal eaten at school by 7-year-old children living in South West England 859 n ¼ 410 packed lunches n ¼ 211 school dinners n ¼ 621 total CWT a P b P c Energy (MJ) d (0.652) (0.593) (0.650) 2.33 o0.001 o0.001 Protein e (%E) 10.6 (10.3, 10.9) 14.4 (13.9, 15.0) 11.8 (11.5, 12.1) o0.001 o0.001 Fat (%E) 39.6 (7.5) 38.8 (7.5) 39.3 (7.5) p Carbohydrate (%E) 49.3 (8.2) 46.3 (7.9) 48.3 (8.2) X50 o0.001 o0.001 Saturated fatty acids (%E) 16.2 (5.0) 12.0 (4.3) 14.8 (5.2) p11 o0.001 o0.001 Monounsaturated fatty acids (%E) 13.2 (3.4) 13.7 (4.0) 13.4 (3.6) Polyunsaturated fatty acids e (%E) 5.7 (5.4, 6.1) 7.2 (6.8, 7.7) 6.2 (5.9, 6.5) o0.001 o0.001 Trans fatty acids (g/mj) (0.190) (0.165) (0.183) Sugar f (%E) 20.9 (20.0, 21.8) 14.2 (13.3, 15.2) 18.5 (17.8, 19.2) p11 g o0.001 o0.001 Starch f (%E) 26.6 (25.9, 27.4) 30.5 (29.4, 31.6) 28.0 (27.3, 28.5) o0.001 o0.001 Non-starch polysaccharide f (g/mj) 1.28 (1.22, 1.34) 1.73 (1.64, 1.82) 1.42 (1.37, 1.48) o0.001 o0.001 Sodium f (mg/mj) 355 (346, 364) 326 (307, 346) 345 (336, 354) Potassium e (mg/mj) 213 (206, 221) 354 (339, 369) 253 (245, 262) o0.001 o0.001 Calcium e (mg/mj) 74.8 (71.5, 78.3) 68.9 (64.2, 74.0) 72.8 (70.0, 75.6) Copper e (mg/mj) (0.101, 0.109) (0.101, 0.110) (0.102, 0.108) Magnesium e (mg/mj) 22.6 (21.8, 23.4) 25.5 (24.8, 26.3) 23.5 (23.0, 24.2) o0.001 o0.001 Phosphorus e (mg/mj) (111.6, 118.7) (136.7, 144.7) (120.3, 126.2) o0.001 o0.001 Iron e (mg/mj) (0.914, 0.969) (0.973, 1.048) (0.942, 0.986) Zinc e (mg/mj) (0.595, 0.637) (0.807, 0.888) (0.666, 0.707) o0.001 o0.001 Selenium f (mg/mj) 9.19 (8.80, 9.60) 5.36 (4.95, 5.78) 7.77 (7.45, 8.11) o0.001 o0.001 Iodine e (mg/mj) 10.6 (10.0, 11.2) 15.1 (13.9, 16.5) 12.0 (11.4, 12.6) o0.001 o0.001 Retinol f (mg/mj) 47.9 (42.8, 53.3) 28.5 (24.5, 32.8) 40.8 (37.2, 44.5) o0.001 o0.001 Carotene f (mg/mj) 101 (88, 116) 239 (190, 295) 142 (124, 160) o0.001 o0.001 Retinol equivalents f (mg/mj) 71.4 (64.9, 78.3) 80.7 (69.6, 92.6) 74.5 (68.8, 80.5) Vitamin D f (mg/mj) 0.28 (0.25, 0.31) 0.32 (0.29, 0.36) 0.29 (0.27, 0.32) Vitamin E f (mg/mj) 1.43 (1.35, 1.50) 1.22 (1.05, 1.18) 1.32 (1.26, 1.37) o0.001 o0.001 Thiamin e (mg/mj) (0.134, 0.146) (0.142, 0.160) (0.139, 0.149) Riboflavin f (mg/mj) (0.120, 0.134) (0.113, 0.127) (0.120, 0.130) Niacin equivalents e (mg/mj) 2.87 (2.77, 2.97) 3.53 (3.37, 3.71) 3.08 (2.99, 3.17) o0.001 o0.001 Vitamin B f 6 (mg/mj) (0.160, 0.178) (0.238, 0.263) (0.187, 0.203) o0.001 o0.001 Vitamin B f 12 (mg/mj) (0.210, 0.262) (0.308, 0.387) (0.249, 0.294) o0.001 o0.001 Folate e (mg/mj) 18.6 (17.8, 19.5) 21.4 (20.2, 22.7) 19.5 (18.8, 20.3) o Vitamin C f (mg/mj) 6.70 (5.77, 7.70) 6.22 (5.53, 6.94) 6.53 (5.88, 7.23) a CWT is the Caroline Walker Trust recommendations (Crawley, 2005). b P by unpaired t test. c P by analysis of variance, adjusted for highest maternal educational level (n ¼ 608). d All P-values for energy intake also adjusted for sex. e Geometric mean shown as nutrient intake transformed to the natural logarithm. f Geometric mean shown as nutrient intake transformed to the square root. g Recommendations relate to non-milk extrinsic (NME) sugars, but figures shown are for total sugar. zinc, iodine, carotene, vitamin B 6 and vitamin B 12, and lower mean intakes of total fat, SFA, TFA, sugar, selenium, retinol and vitamin E. Thus, the PUFA-to-SFA ratio was much higher in school dinners (0.66) than in packed lunches (0.39). However, although the iron and thiamin density of school dinners was higher than that of packed lunches, owing to the lower energy content of school dinners, absolute intakes of iron and thiamin were lower. Furthermore, although the niacin equivalent and folate density of school dinners was higher than that of packed lunches, their lower energy content meant that there was no difference in absolute intakes. These results were largely unchanged on adjusting for maternal educational level. Comparison with guideline nutrient intakes Tables 2 and 3 also show guideline nutrient intakes for school meals taken from the CWT recommendations or from the RNI. The only CWT recommendations that were met by children in both groups were for protein and vitamin C intake. Intakes of energy, NSP, calcium, iron and folate were below the recommendations in both groups. Meals eaten at school also compared unfavorably in relation to the RNI, being less than recommended in both groups for zinc, copper, magnesium, iodine and riboflavin. Energy percentages from total fat and SFA were above the recommended maximum levels, and that from carbohydrate was slightly too low. Nutrient density of food consumed over the whole day Table 4 shows the mean nutrient densities over the whole day that a meal at school was eaten. Several nutrient intakes remained associated with school meal type MUFA, PUFA, potassium, iodine and zinc intakes were all higher across the whole day among children eating school dinners, whereas

5 860 Table 3 Absolute nutrient intakes at lunchtime (mean (s.d.) or geometric mean (95% CI)), according to type of school meal eaten at school by 7-yearold children living in South West England n ¼ 410 Packed lunches n ¼ 211 School dinners n ¼ 621 total CWT/DRV a P b P c Protein (g) 14.7 (6.1) 16.4 (5.1) 15.3 (5.8) X o0.001 Fat (g) 24.2 (8.7) 20.5 (7.9) 22.9 (8.6) p21.7 o0.001 o0.001 Carbohydrate (g) 68.5 (22.1) 55.2 (18.4) 64.0 (21.9) X74.3 o0.001 o0.001 Saturated fatty acids d (g) 9.4 (9.0, 9.8) 5.9 (5.5, 6.3) 8.1 (7.8, 8.5) p6.8 o0.001 o0.001 Monounsaturated fatty acids (g) 8.1 (3.3) 7.2 (3.1) 7.8 (3.2) Polyunsaturated fatty acids d (g) 3.7 (3.5, 3.9) 3.9 (3.6, 4.2) 3.8 (3.6, 3.9) Trans fatty acids d (g) (0.759, 0.856) (0.571, 0.692) (0.706, 0.783) o0.001 o0.001 Sugar d (g) 28.4 (27.0, 29.8) 17.0 (15.7, 18.4) 24.3 (23.1, 25.3) p18.36 f o0.001 o0.001 Starch (g) 38.0 (13.6) 36.5 (12.5) 37.5 (13.3) Non-starch polysaccharide d (g) 2.81 (2.65, 2.96) 3.17 (3.00, 3.35) 2.93 (2.81, 3.05) X Sodium (mg) 805 (291) 627 (251) 745 (290) p655 o0.001 o0.001 Potassium d (mg) 481 (460, 503) 666 (634, 699) 541 (522, 560) X667 o0.001 o0.001 Calcium e (mg) 160 (151, 169) 125 (114, 137) 147 (140, 155) X193 o0.001 o0.001 Magnesium e (mg) 48.3 (46.1, 50.6) 46.3 (44.0, 48.6) 47.6 (45.9, 49.3) X Phosphorus d (mg) 259 (248, 270) 264 (251, 276) 280 (252, 269) Iron d (mg) 2.10 (2.02, 2.19) 1.90 (1.81, 2.00) 2.03 (1.97, 2.10) X Zinc e (mg) 1.32 (1.26, 1.38) 1.53 (1.44, 1.63) 1.39 (1.33, 1.44) X2.3 o0.001 o0.001 Selenium d (mg) 20.2 (19.2, 21.2) 9.8 (9.1, 10.6) 16.3 (15.5, 17.1) X10 o0.001 Iodine e (mg) 22.7 (21.3, 24.3) 27.4 (24.7, 30.4) 24.2 (22.9, 25.6) X Retinol d (mg) 107 (94, 120) 56 (48, 65) 88 (79, 97) o0.001 o0.001 Carotene d (mg) 217 (190, 246) 429 (345, 522) 281 (249, 315) o0.001 o0.001 Retinol equivalents d (mg) 157 (141, 173) 149 (130, 171) 154 (142, 167) X Vitamin D d (mg) 0.62 (0.56, 0.68) 0.62 (0.55, 0.69) 0.62 (0.57, 0.66) Vitamin E d (mg) 3.1 (3.0, 3.3) 2.1 (1.9, 2.3) 2.8 (2.6, 2.9) o0.001 o0.001 Thiamin e (mg) 0.30 (0.29, 0.31) 0.27 (0.25, 0.29) 0.29 (0.28, 0.30) X Riboflavin d (mg) 0.28 (0.26, 0.29) 0.23 (0.21, 0.24) 0.26 (0.25, 0.27) X0.33 o0.001 o0.001 Niacin equivalents e (mg) 6.14 (5.87, 6.43) 6.40 (6.05, 6.77) 6.23 (6.01, 6.45) X Vitamin B d 6 (mg) 0.37 (0.35, 0.39) 0.45 (0.43, 0.48) 0.40 (0.38, 0.41) X0.33 o0.001 o0.001 Vitamin B d 12 (mg) 0.51 (0.46, 0.57) 0.66 (0.58, 0.74) 0.56 (0.52, 0.61) X Folate e (mg) 39.9 (37.8, 42.1) 38.7 (36.1, 41.4) 39.5 (37.8, 41.2) X Vitamin C d (mg) 14.2 (12.3, 16.2) 11.4 (10.2, 12.8) 13.2 (11.9, 14.6) X a Guideline nutrient intakes are taken from the Caroline Walker Trust (CWT) where available (shown in bold), or from 1/3 of the Reference Nutrient Intake (RNI) from the report on Dietary Reference Values (DRV), or for sodium from the SACN report on Salt and Health. b P analysis of variance adjusting for sex. c P by analysis of variance adjusting for sex and maternal educational level (n ¼ 608). d Geometric mean shown as nutrient intake transformed to the square root. e Geometric mean shown as nutrient intake transformed to the natural logarithm. f Recommendations relate to Non-milk extrinsic (NME) sugars, but figures in table are for total sugars. SFA, sugar, selenium and vitamin E intakes were all higher among children eating packed lunches. Foods eaten at lunchtime Table 5 shows the types of food/drink included at lunchtimes in the two different meal types eaten by boys and girls. Fried/ roast potatoes, cooked vegetables and puddings, and ice cream were the three most commonly consumed foods in school dinners. Buns, cakes and pastries; sausages, burgers and pies; pasta, rice and pizza, etc. and baked beans were all also eaten by 20 30% of children. In contrast, the five most commonly consumed foods in packed lunches were white bread, fat spreads, crisps, sweet biscuits (usually containing chocolate) and fruit. Almost five times more white than wholemeal bread was eaten. Around a quarter of children ate confectionery (mainly chocolate-based) as part of their packed lunch. Most children had a soft drink, but reduced sugar soft drinks were more popular than those containing sugar. However, 17% of boys and 9.0% of girls ate sugar/ preserves in their packed lunch, commonly as a jam sandwich. Total fruit and vegetable intake (including baked beans and fruit juice) in boys and girls, respectively, was 50.7 and 46.6 g for those having school dinners, and 53.7 and 66.6 g among those having packed lunches. Although intakes of vegetables were considerably greater than fruit among those children having school dinners, the converse was true among children having packed lunches. The guidelines recommend that lunchtime meals should include one portion of fruit and one portion of vegetables, but intake clearly falls well short of this, irrespective of meal type. The current recommendation on fruit and vegetable intakes for adults is five portions a day, which equates to around 45 g of fruit and vegetables per MJ of energy intake. As these children, have a mean energy intake of 7.0 MJ, at age 7 the equivalent amount of fruit and vegetables they need to eat is 314 g. Aiming to take a third of this at lunchtime would

6 Table 4 Energy intake and nutrient densities (mean (s.d.) or geometric mean (95%CI)), either as percentage of energy (%E) or per unit of energy (MJ) over the whole day, according to type of meal eaten at school by 7-year-old children living in South West England 861 n ¼ 410 packed lunches n ¼ 211 school dinners n ¼ 621 total P a P b Energy (MJ) 7.02 (1.37)) 6.88 (1.40) 6.98 (1.38) Protein (%E) 13.1 (2.4) 13.4 (2.5) 13.2 (2.4) Fat (%E) 35.5 (5.1) 35.8 (4.7) 35.6 (5.0) Carbohydrate (%E) 51.5 (5.4) 50.9 (5.1) 51.3 (5.3) Saturated fatty acids (%E) 14.8 (3.2) 14.1 (3.1) 14.6 (3.2) Monounsaturated fatty acids (%E) 11.8 (2.2) 12.2 (2.0) 12.0 (2.1) Polyunsaturated fatty acids c (%E) 5.1 (4.9, 5.3) 5.5 (5.3, 5.7) 5.2 (5.1, 5.4) Trans fatty acids (g/mj) 0.35 (0.11) 0.34 (0.11) 0.35 (0.11) Sugar (%E) 25.2 (5.8) 23.9 (5.8) 24.8 (5.8) Starch (%E) 25.9 (4.9) 26.6 (4.8) 26.1 (4.9) Non-starch polysaccharide c (g/mj) 1.38 (1.34, 1.43) 1.45 (1.39, 1.51) 1.40 (1.37, 1.44) Sodium (mg/mj) 327 (71) 316 (77) 323 (74) Potassium c (mg/mj) 301 (295, 307) 325 (316, 334) 309 (304, 314) o0.001 o0.001 Calcium (mg/mj) 113 (37) 112 (33) 113 (35) Copper c (mg/mj) (0.100, 0.106) (0.097, 0.104) (0.100, 0.105) Magnesium c (mg/mj) 28.2 (27.6, 28.8) 27.7 (27.0, 28.4) 28.0 (27.5, 28.5) Phosphorus (mg/mj) 149 (30) 151 (27) 150 (29) Iron c (mg/mj) 1.13 (1.10, 1.15) 1.10 (1.06, 1.13) 1.12 (1.10, 1.14) Zinc c (mg/mj) 0.80 (0.78, 0.82) 0.84 (0.81, 0.87) 0.82 (0.80, 0.83) Selenium c (mg/mj) 7.32 (7.09, 7.56) 6.19 (5.92, 6.48) 6.92 (6.73, 7.10) o0.001 o0.001 Iodine c (mg/mj) 19.2 (18.3, 20.0) 20.7 (19.4, 22.0) 19.7 (19.0, 20.4) Retinol c (mg/mj) 41.4 (39.2, 43.8) 40.9 (37.4, 44.8) 41.2 (39.3, 43.3) Carotene c (mg/mj) 152 (139, 166) 162 (142, 184) 155 (138, 167) Retinol equivalents c (mg/mj) 75.6 (71.8, 79.6) 78.9 (73.4, 84.9) 76.7 (73.6, 80.0) Vitamin D d (mg/mj) 0.30 (0.28, 0.31) 0.30 (0.28, 0.32) 0.30 (0.29, 0.31) Vitamin E d (mg/mj) 1.11 (1.07, 1.15) 1.03 (0.99, 1.08) 1.08 (1.05, 1.11) Thiamin c (mg/mj) (0.180, 0.192) (0.173, 0.188) (0.179, 0.189) Riboflavin (mg/mj) (0.085) (0.072) (0.080) Niacin equivalents (mg/mj) 3.78 (0.89) 3.72 (0.86) 3.76 (0.88) Vitamin B 6 (mg/mj) (0.077) (0.076) (0.077) Vitamin B d 12 (mg/mj) (0.433, 0.475) (0.448, 0.514) (0.445, 0.481) Folate (mg/mj) 28.3 (10.0) 27.6 (8.6) 28.0 (9.5) Vitamin C d (mg/mj) 10.3 (9.5, 11.0) 9.8 (8.9, 10.8) 10.1 (9.5, 10.7) a P-value by unpaired t-test. b P-value by analysis of variance, adjusted for highest maternal educational level. c Geometric mean shown as nutrient intake, transformed to the natural logarithm. d Geometric mean shown as nutrient intake, transformed to the square root. produce a 105 g target, around twice the recorded intake for both school dinners and packed lunches. Focusing on packed lunches: only 3.5% included all five food items recommended by the FSA (i.e. starchy food, protein food, dairy item, vegetable/salad and fruit), and nearly half (44.3%) included two or less of the recommended items. All but 8% included a starchy food; however, 31% did not include a protein food, and less than half included a fruit (41%), a dairy or milk-based food (49.7%) or a vegetable/ salad (16%). Discussion We have examined the diets of primary school children in 1999/2000, and found that at that time both school dinners and packed lunches fell short of dietary guidelines. Both exceeded the recommended proportion of energy from total fat and SFA, and provided less than the recommended levels of fibre and several vitamins and minerals. These results confirm the need to introduce improved standards for school dinners. Furthermore, there were marked differences in the food and nutrient content of packed lunches compared to school dinners. The sugar and saturated fat content of packed lunches was higher and the content of most vitamins and minerals lower than school dinners, giving packed lunches, on the whole, a less healthy nutrient profile. Some of these differences persisted over the whole day s nutrient intake and were large enough to be plausibly associated with modification of outcomes of importance to public health (Whincup et al, 2005). The differences in nutrient intake were robust to adjustment for maternal education, suggesting that they are directly related to the types of school meal consumed, rather than merely reflecting social patterning of nutrient intake. Both types of school meals fell short of the 1991 recommended energy intake, however, given the rapidly emerging problem of childhood obesity, it is debatable whether the current energy intake recommendations

7 862 Table 5 Mean intake (g) and percentage of meals containing each type of food/drink according to type of lunch eaten at school by 7-year-old children living in South West England Boys Girls School (n ¼ 249 meals) Packed (n ¼ 433 meals) School (n ¼ 192 meals) Packed (n ¼ 368 meals) Mean % Mean % Mean % Mean % White bread Wholemeal bread Other bread a Fat spreads Cow s milk Yoghurt and fromage frais Cheese Eggs and egg dishes Fruit Fruit juice Nuts Cooked vegetables Salad Baked beans Fried/roast potatoes and chips Other potatoes Pasta, rice, pizza etc Coated white fish Other fish Coated chicken and turkey Chicken and dishes Meat and dishes b Ham and bacon Sausages, burgers and pies Puddings and ice cream Buns, cakes, pastries and fruit pies Sweet biscuits Savoury biscuits Chocolate and other sweets Sugar and preserves Crisps and savoury snacks Normal squash/fizzy drinks Low sugar squash/fizzy drinks a Other bread ¼ Brown bread, granary bread and other bread. b Beef, lamb, pork and liver and dishes containing these meats. remain appropriate. It is, therefore, likely that raising the children s energy intakes at lunchtime, without a concurrent increase in physical activity levels, would be counterproductive. Our results confirm some of the changes needed to improve school dinners, in particular a reduction in fat content by using less fried/coated foods (potatoes, poultry and fish) and less processed meat dishes (sausages, burgers and pies); an increase in fruit and vegetable content; and an increase in starch content. However, despite the high usage of processed fatty foods, school dinners had a less atherogenic nutrient profile than packed lunches, with a higher PUFA:SFA ratio and lower TFA content (Andersen et al, 1979; Mensink and Katan, 1990). The differences are likely to increase with the planned improvement in school dinners, and our results highlight that improving the composition of packed lunches is equally important. The fat, sugar and sodium content of packed lunches were all high, reflecting the wide scale use of biscuits, confectionery, cakes and crisps. Packed lunches also contained only half the recommended amount of fruit and vegetables, contributing to their low potassium content. The combination of a low potassium and high sodium intake by children consuming packed lunches is of concern as this has been associated with the development of raised blood pressure in childhood (Geleijnse et al, 1990), and blood pressure tracks strongly from childhood onwards (De Swiet et al, 1980; Sanchez-Bayle et al, 1999). We could find only one other study that directly compared packed lunches and school dinners (Ruxton et al, 1996). This 1991 study of Scottish 7-year-olds concluded that packed lunches had a slightly better nutrient profile than school dinners, although they also found that neither type of meal met the guidelines. The quality of the school dinners in the Scottish study was worse than those in the current study, being higher in sugar (24.8 vs 17.0 g) and fat (42.3% of energy vs 38.8%) and lower in starch, possibly reflecting

8 regional differences or an improvement in school dinner quality in the intervening decade. Conversely, the amount of fat in the packed lunches eaten in Scotland was lower than those eaten in Avon (36.4 vs 39.6% of energy). A consistent finding between the studies was that packed lunches contained much more sugar than school dinners (in England 28.4 and 17.0 g per meal, and in Scotland 37.4 and 24.8 g). No information on the types of food eaten by the children was presented. Information on school dinners eaten by 4 10 year-olds in 1997 was presented in the National Diet and Nutrition Survey of 4 18 year-olds (Gregory and Lowe, 2000), and the 2004 School Lunch Box Survey presented data on packed lunches eaten by a national sample of 9 11 year-olds (Jefferson and Cowbrough, 2004). In both cases, results for food and nutrient intakes were similar to our own, with slightly higher energy intakes attributable to the greater mean age of the children surveyed. There are a number of limitations to the current study. The dietary assessment method chosen was an unweighed food record, whereas weighed intakes are generally considered to be the gold standard method. However, we feel that foods eaten at lunchtime are particularly suitable for assessment by unweighed food records as school dinners are served out in standard portion sizes, and packed lunches consisted largely of items that occur in individual units, such as yoghurts, packets of crisps, pieces of fruit, biscuits etc., making estimation of quantities eaten much easier. The use of unweighed records for dietary assessment have been shown to perform well in comparison with weighed records (Bingham et al, 1994). The food and drinks taken by these 7-year-old children were recorded by the parents in discussion with their child, and this may have led to some inaccuracy regarding meals where the parent was not present. However, packed lunches are generally provided by the parents, and leftovers often returned home in the lunch box, thus making them relatively easy to record. Food eaten for school dinners may be more difficult for parents to establish. However, menus are often published for parents to read, thus aiding the child s recall of the meal. Although the dietary records kept for these children covered three days, these were not necessarily all school days so that the nutrient assessments were based on 1 or 2- day records for most children. Using less diaries for each person will lead to less reliable estimates of individual intakes because of day-to-day variations between persons. However, only group comparisons have been made in this analysis with adequate numbers in each group. It is possible that the differences we have observed between packed lunches and school dinners are an artefact of cohort attrition. The results were, however, almost unchanged on adjusting for maternal education, which would argue against this. Furthermore, we feel that cohort attrition would be more likely to reduce the observed differences between school dinners and packed lunches, rather than create them. The same school meals are offered to all children. However, as the parents provide the packed lunches, these are more likely to be affected by the differential drop out of the less educated groups from the survey who are likely to have consumed a poorer quality diet (North and Emmett, 2000; Rogers et al, 2003). This study was conducted in 1999/2000 before the current guidelines on school dinners came into force. It seems likely that the difference in quality between school dinners and packed lunches will be greater now than at the time of this survey. In conclusion, we have found that both types of meal previously eaten at school compared unfavorably with recommended nutrient intakes, but packed lunches performed less well than the school dinners provided at the time. As packed lunches are eaten by the majority of British schoolchildren, improving them is arguably more important than improving school dinners. Negative publicity about school dinners may have resulted in children switching to packed lunches, possibly resulting in a deterioration rather than an improvement in their nutrient intakes. As nutritional standards for school dinners have recently been introduced, an improvement might be expected currently. However, to protect the children who consume packed lunches, it may be necessary to introduce some regulations about the types of food that children are allowed to bring with them into schools. Schools may need to work with parents and children to improve acceptance of better nutritional quality in both types of meal as changing eating habits is not necessarily straight forward (Cho and Nadow, 2004). A change in the attitude to food, of the wider community and mass media, may be necessary to support children in eating more healthily. Acknowledgements We are extremely grateful to all the families who took part in this study, the midwives for their help in recruiting them, and the whole ALSPAC team, which includes interviewers, computer and laboratory technicians, clerical workers, research scientists, volunteers, managers, receptionists and nurses. The UK Medical Research Council, the Wellcome Trust and the University of Bristol provide core support for ALSPAC. This publication is the work of the authors who also serve as guarantors for the contents of this paper. References Andersen GE, Lifschitz C, Friis-Hansen B (1979). 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