Among the 189 schools without a canteen, 22.8% (n=43) reported the previous existence of such an establishment. The reasons given for the absence of a canteen were: the provision of free meals in public schools, through the National School Meals Programme (Programa Nacional de Alimentação Escolar, PNAE) (n=94; 49.7%); implications and difficulties brought about by the introduction of Law nº 12.061/2001 (8) (n=43; 22.7%); financial reasons (n=23; 12.2%); guidance from the Municipal Secretaries for Education, with the encouragement of the PNAE, to the detriment of canteens (n=16; 8.5%) and the fact that the school had a majority of students from low-income families (n= 13; 6.9 %).

With regard to the administration of the canteens, it was found that among the 156 establishments identified, corresponding to 45.2% of the sample, 83 (53.2%) were the responsibility of the school itself, with the remaining canteens being tendered services.

Schools with canteens: products sold

Table 2 characterises the items sold in the canteens, according to educational sector. A high percentage of response was found for each item in Table 2, with the lowest percentage being 96.8%.

Without separating by sector, it can be seen from Table 2 that more than half of the canteens provided baked goods (n=130; 83.9%), pizzas (n=113; 72.9%), cakes and gateaux (n=101; 65.2%), plain crackers/biscuits (n=95; 61.3%) and hot dogs (n=88; 56.8%). In relation to sweets, chocolates (n=78; 50.6%) and others desserts (e.g.: puddings, mousses) (n=72; 48.0%) were the items that exhibited the highest total frequency (Table 2). With regard to drinks, it was noted that more than half of the canteens sold milk chocolate (n=117; 76.5%), juices (n=102; 66.7%) and mineral water (n=95; 61.3%) (Table 2). There was a significant difference among the sectors in the sale of the majority of foods, that is, 22 of the 38 items listed in Table 2 presented a p<0.05.

Table 3 lists only those items from Table 2 with a significant difference among the sectors, and demonstrates that the canteens of private schools stood out in relation to the public state and municipal schools with the sale of cereal bars, cakes and gateaux, cheese bread, fruit salads, puff pastries, sandwiches in general and sachets of industrialised sauces (p<0.05 for all items).

With regard to sweets, the canteens in the private institutions differed from the municipal schools in the sale of sweetened nuts (p=0.022) and chocolates (p=0.014). Compared to the state schools, the private establishments more often sold jelly (p<0.001). Concerning the public institutions, the state school canteens stood out through the sale of chocolates (p=0.002), while the municipal schools were notable for the more frequent sale of jelly (p=0.005) (Table 3).

The majority of the canteens (n=105; 68.2%) were found to be in Class 4 (level 50 on the scale), meaning that they complied with the Law in relation to not selling the previous items, besides hard candies, lollipops and chewing gum, and packaged snacks (Table 4).

In order to comply with the Law on the previous items, as well as on the items referring to juices and the daily availability of two fruits, canteens should present a level of compliance of at least 70 (Class 5: in addition to not selling the previous items they also should not sell juices), and level 80 (Class 6: besides not selling the previous items and juices, they should provide fruits on a daily basis). It is notable that no establishment reached these levels of compliance with the Law (Table 4).

The mean value of compliance with the Law was not significantly different among the sectors (municipal: 51.05; state: 48.26 and private: 51.30) (ANOVA=0.059).

Involvement of the school management and of those responsible for the canteens in promoting a healthy school snack

Table 5 shows some of the actions carried out to promote healthy school snacks. The response rate for the following questions was = 95.0%, with the frequencies relative to the data also given.

The majority of those responsible for the canteens (n=119; 81.5%) reported that the school management suggested or limited some of the products sold, with a difference existing between sectors (p=0.037). In the private school sector management was 3.22 (95%CI=1.16-8.92; p=0.024) times more likely to do this compared to the state sector (Table 5). The majority of those interviewed referred to items prohibited under Law nº 12.061/2001 (8) (n=203; 77.8%) as foods and/or drinks limited or prohibited by the management. Chocolates and sweets in general appeared next (n=30; 11.5%).

Among those responsible for the canteens, 15.8% (n=24) reported that the school carried out nutritional education activities in the canteen and 28.7% (n=43) stated that they had developed some kind of activity with the school to promote healthy snacks, with no significant difference among the different sectors (p=0.105) (Table 5). Moreover, 14.7% (n=22) of those responsible reported promoting the canteen with educational materials about healthy eating (Table 5), and the presence of a notice board on diet having been observed next to the canteen in 7.1% (n=11) of the establishments.

The majority of those responsible for the canteens considered their establishment “healthy” (n=95; 60.9%), followed by the option “canteen in the process of becoming healthy” (n=47; 30.1%), with no significant difference existing between the judgement of the respondents from the different sectors (p=0.194).

In relation to the difficulties that those responsible for the canteens encountered in implementing a healthy canteen, the following distribution was observed: financial difficulties (n= 53; 34.0%); lack of support from the school community (n=27; 17.3%); low acceptance by the students (n=18; 11.5%); free school meals offered in the public schools (n=15; 9.6%); lack of infrastructure, of time and of staff (n=15; 9.6%); lack of training of those involved in food preparation (n=10; 6.4%) and, less cited, a lack of healthy dietary options (n=6; 3.8%).

DISCUSSION

Positive factors were revealed in relation to the sale of foods in the canteens. For example, it is noteworthy that the greater part of the establishments offered baked savouries goods, which are options recommended for healthy canteens (9,10,16).

Based on the examination of the group of items analysed by IRT, it can be seen that the majority of canteens (68.2%) did not sell fried snacks, soft drinks, industrialised popcorn, hard candies, lollipops and chewing gum, and industrialised packaged snacks. The items that were found to present the greatest difficulty in being aligned with the Law were artificial juices and the daily sale of two seasonal fruits.

While the average level of compliance with the Law was lower in the canteens in state schools, no difference was found in the ANOVA. This result may indicate a marginal effect, which could be significant if the sample and/or the number of items were larger.

Attention should be drawn to the fact that many canteens offered items considered to be of low nutritional value, such as filled biscuits, puff pastry savouries, industrialised sauces and sweets in general. Foods and drinks considered healthy, such as fruits, wholegrain sandwiches, yogurt and 100% fruit juice appeared less often in the canteens of the public schools.

In general, the canteens of the private schools presented a greater variety of items sold. However, the most noteworthy feature of these canteens was not just the sale of foods considered healthy. Items such as puff pastry savouries and industrialised sauces were also more frequently found in these institutions.

The “Ten Steps to the Promotion of a Healthy Diet in Schools” (16), proposed by the Ministry of Health, states that foods considered unhealthy include hard candies; lollipops; chewing gum; biscuits, especially filled; soft drinks; juices or squashes; fried foods; mayonnaise; savouries with sausages and ham/pressed ham; savoury snacks in packets; industrialised popcorn and others with the profile described above. It can be seen that the foods prohibited by Law nº 12.061/2001 (8) corroborate those listed in the “Ten Steps” (16).

The foods sold are not always appropriate for the school students, and can interfere in the consumption of meals provided by the PNAE (17). In addition, the substitution of calories obtained from traditional foods by products of low nutritional value and high caloric content may be contributing to the development of overweight and obesity (18).

Internationally, research has repeatedly shown that state and federal regulation of the foods sold in schools, as well as the inspection of these remains minimal, showing the need for intervention measures and well-structured local, public school policies (19,20).

A systematic review of school food policies reported that there was very little evidence and a lack of consistent findings for the effectiveness of regulating food and beverage availability, as well as little evaluation of their impact on body mass index (BMI). Since schools have been proposed worldwide as a major setting for tackling childhood obesity, it is vital that future policy evaluations measure the long term effectiveness of school food policies in tackling both dietary intake and overweight and obesity. Few school food policies on a national or large scale have been introduced and assessed around the world, and all feature studies performed in the United States and Europe (21).

A study in the United States with 1088 school students showed that in schools which have strategies related to healthy school diets, the students reported buying snacks on average 0.5 days/week, versus 0.9 days/week in institutions without these actions (p<0.001) (22). A study of school canteens in 200 institutions in New Zealand highlighted the fact that 16.5% of schools had strategies for the promotion of healthy school eating. The foods most frequently found in canteens were gateaux (79.0%) and sausage rolls (54.5%) (23). In Australia, research on canteens found that special days with the offer of a greater variety of foods, special offers and marketing were successful strategies for driving sales, while the sale of fruits and salads were unsuccessful strategies (24).

It is vital to recall that the educational role of the school and other members of the school community places this institution in a position of fundamental relevance in terms of dealing with the construction and consolidation of healthy eating practices (2,25). The WHO considers the due care of nutrition in schools to be an effective investment for future generations (25), and that school canteen owners should be made aware of this context (6).

According to the Ministry of Health, the support of those responsible for canteens is fundamental, as the training of such staff can constitute a strategy that will guarantee the economic viability of these establishments and the possibility of them being transforming into spaces for the promotion of health (6). In this study, it was found that a small number of those responsible for canteens developed educational activities to promote healthy eating habits.

The notice board on diet was present in only 7.1% of the establishments, despite this being required under Law nº 12.061/2001 (8). On the other hand, according to the IRT assessment, schools with a lower level of compliance with the Law were precisely those which had a notice board. Such a finding should lead to a reflection on the real aim of this, which goes beyond the mere legal requirement of displaying the notice board near the canteen. It can be seen that there is a need for training and raised awareness in those involved in the canteen, so that this educational instrument can actually become an ally in the process of promoting healthy eating in schools.

The project “The School Promoting Healthy Dietary Habits”, by the UNB, includes training for owners of school canteens. In the results for the assessment of the implantation of a healthy canteen, the authors observed more positive behaviour on the part of the proprietor only in aspects directly related to the canteen, such as the promotion of/special offers on healthy snacks, indicating that the owners need external support in order to implement and sustain the proposal (11).

While the training of educators and owners of canteens is necessary (11,26), the development of other strategies that guarantee the sustainability of a healthy school environment is also essential (27). In 2007 the Ministry of Health released an official document that detailed the Brazilian experience of healthy eating regulations in the school environment (6). While the initiatives and legislative measures in the state and municipal sectors are laudable, it is necessary to approach this question on the national stage. Interministerial Decree nº 1.010, dated 8th. of May 2006 (28), may be the first step towards the development of actions in this sense.

It is important to emphasise the primordial role of nutritionists and health professionals in the encouragement and implementation of measures to promote healthy diets in schools, providing subsidies for school food policies. Moreover, the inspection of these establishments is necessary, together with educational actions and strategies to improve the dietary habits of those within the school environment.

This study did not investigate the foods sold by street vendors close to schools, nor other forms of informal commerce. It is important to determine if these items comply with Law, since students, even during school hours, can have access to inappropriate foods through this route.

CONCLUSIONS

The application of IRT in this study proved to be particularly interesting. The intention was, firstly, to guide and publicise the production of this kind of indicator in the field of assessment of public policies and other intervention measures. The execution of this methodology opens the way for other studies to be carried out, with different actions, in different locations, in order to obtain a standardised measure for similar macroassessments. Ideally the IRT would be reapplied, with a greater number of items, enabling a better use of the information given and, consequently, greater precision in the estimates of the indexes calculated.

Although the greater part of the canteens did not sell the majority of items prohibited under the state legislation of Santa Catarina, many establishments still offered items considered to be of low nutritional value.

The Law under investigation here is recognised as a strategy to improve the food provided in schools, with the objective of helping schools to develop healthy eating habits and prevent CNTDs. On the other hand, it is acknowledged that the problem of school-age obesity will not be resolved by merely prohibiting caloric foods in schools or by restricting their advertising. The combined action of parents, teachers, health professionals, owners of school canteens, legislators and advertising agencies, among others, is necessary to promote environments and strategies that enable healthy eating habits and that also encourage the practice of physical exercise among students.

Finally, this work underlines the need for further investigation on the theme of diet in schools, considering the scarcity of studies identified in the literature investigated.

COLLABORATORS

C.G. Gabriel, F.A.G Vasconcelos, D.F. Andrade and B.A.S. Schmitz participated in the development of the research. C.G. Gabriel was responsible for processing and analysing the data, and for preparation of the manuscript. F.A.G. Vasconcelos and D.F. Andrade oversaw the methodological design and revised the manuscript. D.F. Andrade contributed to data analysis. B.A.S. Schmitz participated in discussion and final revision of the paper.

REFERENCES

1. World Health Organisation. Escolas Promotoras de Saúde: modelo e guia para a ação: OPAS; 1996. (Série HSS/Silos.)        [ Links ]

2. Moura JBVS, Lourinho LA, Valdês MTM, Frota MA, Catrib AMF. Perspectiva da epistemologia histórica e a escola promotora de saúde. Hist. cienc. saude-Manguinhos 2007;14:489-501.        [ Links ]

3. Ippolito-Shepherd J, Cerqueira MT, Ortega DP. Iniciativa Regional Escuelas Promotoras de la Salud en las Américas. IUHPE – Promotion & Education 2005; XII:220-29.        [ Links ]

4. World Health Organisation. Global strategy on diet, physical activity and health; 2004. (Fifty-seventh World Health Assembly. WHA57.17).        [ Links ]

5. Barreto SM, Pinheiro ARO, Sichieri R, Monteiro CA, Batista Filho M, Schimidt MI et al. Análise da Estratégia Global para Alimentação, Atividade Física e Saúde, da Organização Mundial da Saúde. Epidemiol. Serv. Saúde 2005;14:41-68.         [ Links ]

6. Brazil. Ministério da Saúde. Experiências estaduais e municipais de regulamentação da comercialização de alimentos em escolas no Brasil: identificação e sistematização do processo de construção e dispositivos legais adotados. Brasília: Ministério da Saúde; 2007.        [ Links ]

7. Lei n. 5853, de 04 de junho de 2001. Dispõe sobre os critérios de concessão de serviços de lanches e bebidas, nas unidades educacionais, localizadas no município de Florianópolis. 2001. (cited 2008 Jul 05). Available from: http://www. leismunicipais.com.br/cgi-local/leis2.pl         [ Links ]

8. Lei nº 12.061, de 18 de dezembro de 2001. Dispõe sobre critérios de concessão de serviços de lanches e bebidas nas unidades educacionais, localizadas no Estado de Santa Catarina. Diário Oficial do Estado de Santa Catarina 2001; 18 dez.        [ Links ]

9. Lei nº 14.855 de 19 de outubro de 2005. Dispõe sobre padrões técnicos de qualidade nutricional, a serem seguidos pelas lanchonetes e similares, instaladas nas escolas de ensino fundamental e médio, particulares e da rede pública do Estado do Paraná. (cited 2008 Apr 21). Available from: http://www.pr.gov.br/casacivil/legislacao.shtml        [ Links ]

10. Brazil. Normas para funcionamento de cantinas escolares. Portaria Conjunta COGSP/CEI/DSE, de 23 de março de 2005. (cited 2007 Jul 23) Available from:http://dersv.sites.uol.com.br/port_conj_CEI_cantina.htm.        [ Links ]

11. Schmitz BAS, Recine E, Cardoso GT, Silva JRM, Amorim NFA, Bernardon R, Rodrigues MLCF. A escola promovendo hábitos alimentares saudáveis: uma proposta metodológica de capacitação para educadores e donos de cantina escolar. Cad. Saúde Pública 2008;24:312-22.        [ Links ]

12. Andrade DF, Tavares HR, Valle RC. Teoria da Resposta ao Item: Conceitos e Aplicações. São Paulo: Associação Brasileira de Estatística; 2000.        [ Links ]

13. Embretson SE, Reise SP. Item Response Theory for Psychologists. New Jersey: Lawrence Erlbaum Associates; 2000.        [ Links ]

14. Baker FB. The Basics of Item Response Theory. ERIC Clearinghouse on Assessment and Evaluation 2001. (cited 2008 Sept 10). Available from: http://www.edres.org/irt/        [ Links ]

15. Zimowski MF, Muraki E, Mislevy RJ, Bock RD . BILOG-MG: Multiple-Group IRT Analysis and Test Maintenance for Binary Items. Chicago: Scientific Software, Inc; 1996.        [ Links ]

16. Brazil. Ministério da Saúde. Dez passos para a promoção da alimentação saudável nas escolas; 2004. (cited 2007 Aug 28). Available from:http://dtr2004.saude.gov.br/nutricao/documentos/dez_passos_pas_escolas.pdf.        [ Links ]

17. Sturion G, Silva MV, Ometto AMH, Furtuoso COM, Pipitone MAP. Fatores condicionantes da adesão dos alunos ao Programa de Alimentação Escolar no Brasil. Rev. Nutr. 2005;18:167-81.        [ Links ]

18. Andrade RG, Pereira RA, Sichieri R. Food intake in overweight and normal-weight adolescents in the city of Rio de Janeiro. Cad. Saúde Pública 2003;19:1485-95.         [ Links ]

19. Kann L, Grunbaum J, McKenna ML, Wechsler H, Galuska DA. Competitive foods and beverages available for purchase in secondary schools - selected sites, United States, 2004. J Sch Health 2005;75:370-74.        [ Links ]

20. Probart C, Mcdonnell E, Weirich JE, Hartman T, Bailey-Davis L, Prabhakher V. Competitive foods available in Pennsylvania public high schools. J Am Diet Assoc. 2005; 105:1243-49.        [ Links ]

21. Jaime PC, Lock K. Do school based food and nutrition policies improve diet and reduce obesity? Prev. Med. 2009;48:45-53.        [ Links ]

22. Neumark-Sztainer D, French SA, Hannan PJ, Story M, Fulkerson JA. School lunch and snacking patterns among high school students: associations with school food environment and policies. Int J Behav Nutr Phys Act. 2005;2:14-20.         [ Links ]

23. Carter MA, Swinburn B. Measuring the ‘obesogenic’ food environment in New Zealand primary schools. Health Promot Int. 2004;19:15-20.        [ Links ]

24. Drummond C, Sheppard L. South Australian school canteens 2003: Revisiting the 1990 school canteen/tuckshop survey. Journal of the HEIA (Home Economics Institute of Australia) 2004;11: 13-22.        [ Links ]

25. World Health Organisation. Nutrition-Friendly Schools Initiative (NFSI). Public Health Nutrition 2006;9:658-60.        [ Links ]

26. Gabriel CG, Santos MV, Vasconcelos FAG. Avaliação de um programa para promoção de hábitos alimentares saudáveis em escolares de Florianópolis, Santa Catarina, Brasil. Rev. Bras. Saude Mater. Infant. 2008;8:299-308.        [ Links ]

27. Gonçalves FD, Catrib AMF, Vieira NFC, Vieira LJES. Health promotion in primary school. Interface Comun Saúde Educ. 2008;12:181-92.        [ Links ]

28. Brazil. Portaria Interministerial nº. 1010 de 8 de maio de 2006. Institui as diretrizes para a Promoção da Alimentação Saudável nas Escolas de educação infantil, fundamental e nível médio das redes públicas e privadas, em âmbito nacional. Diário Oficial da União 2006; 9 mai.        [ Links ]