Guidelines Dietary - Eat For Health

Capturing new evidenceNutrition research is continuously evolving and studies are published regularly. Relevant results from high qualitystudies (primarily systematic reviews) assessing food, diet and health relationships that were published afterthe literature review for the Evidence Report (i.e. after 2009) were also considered in the development of theGuidelines. While results from these studies were not graded, and did not influence the evidence statements,they were included in the Guidelines and were deemed warranted to ensure currency.As the Evidence Report only included studies investigating food, diet and health relationships, the results ofother high quality studies published since 2002 were used to update the sections in the Guidelines that provideother information (‘Setting the scene’, ‘How eating a particular food may improve health outcomes’, and ‘Practicalconsiderations’ sections) if they met the following criteria:• the study was a high quality randomised controlled trial, intervention, cohort, or observational study, but not aneditorial or opinion piece (meta-analyses were considered)• the outcome of the study related to some aspect of health or chronic disease• the study results were generalisable to the Australian population• the study was related to foods or the total diet rather than nutrients.While they did not influence the evidence statements or grades, these sources were used to assist in refiningtranslation of the evidence.How the evidence was usedGetting the Guideline wording rightThe final wording of each Guideline was developed by the Working Committee through a consensus approach,based on the information gained from the five key sources discussed above. Each Guideline is considered to beequally important in terms of public health outcomes.For example, to translate all available evidence regarding consumption of vegetables and health outcomes into aguideline recommendation the following evidence was considered:• the graded evidence statements (from Grade A through to C) about the relationship between consumption ofvegetables and various health outcomes 33• the importance of vegetables as a source of key nutrients in the Australian diet from the Food ModellingSystem 9 and the NRV Document 8• the relatively low energy content of vegetables 8,9• findings of international authoritative reports including the World Cancer Research Fund report (WCRF Report)(see Appendix F) 43• information provided in the 2003 edition of the dietary guidelines. 36Assessment of all available sources of evidence confirmed the importance of consuming vegetables for promotinghealth and wellbeing. The Working Committee translated this evidence into the guideline recommendation to ‘eatplenty of vegetables’.Using evidence statementsThe graded evidence statements from the Evidence Report are included in the section titled ‘Evidence’ undereach guideline recommendation. These sections also include relevant ungraded referenced evidence from theother four key evidence sources to ensure comprehensiveness and currency. The Evidence sections provide thebasis of the scientific information that was translated to form the guideline recommendation at the beginning ofeach chapter.To ensure the Guidelines are realistic, practical and achievable, the scientific and social context for each guidelinerecommendation was considered, along with potential mechanisms through which particular dietary patternsmay influence health, to help assess the plausibility of the associations described in the Evidence sections.This information originated predominantly from the previous dietary guidelines series, updated by narrativereviews of additional literature sourced from authoritative reports, from the Food Modelling System, 9 the NRVDocument 8 and high quality studies published since the 2003 edition of the dietary guidelines.IntroductionNational Health and Medical Research Council7