Professing public health nutrition.

Clarity of purpose is essential for a discipline and its profession: to advocate for public and political support; to attract and socialise students and novices. Three seminal contributions to this issue by Roger Hughes will help the international community of public health nutrition to benchmark its development as a subject and profession, related to and yet distinct from public health and health promotion. Hughes’ paper entitled ‘Definitions for public health nutrition: a developing consensus’ reports how consensus rapidly emerged around the nature of, and competencies required for, the practice of public health nutrition among key informants in Australia, the European Union, and the USA. Hughes provides the first evidence base for the identification of the core conceptions of the discipline. He offers flexibility for adaptive communication tailored for particular audiences and purposes. Perhaps there is a further need to express the relationship between public health nutrition and nutrition science that underpins it? A draft report by a joint working party of the (British) Nutrition Society and the Association of Professors of Human Nutrition seeks to build a consensus around the nature of nutrition science in order to promote, protect and enhance the quality of courses of study. This draft report further suggests the core knowledge and competencies required for professional registration in nutrition science. All nutritionists from public health and other specialisms are invited to comment on this draft report (www.nutsoc.org.uk). Should there be clear distinction between nutrition science and public health nutrition or should we explicitly strengthen interdisciplinary links within nutrition? The answers to these questions may have repercussions for the practice of nutrition worldwide. Hughes reports on ‘A conceptual framework for intelligence-based public health nutrition workforce development’. His conceptual framework provides an opportunity to critically appraise models for workforce planning and to engage with the nature of expertise. Specialist expertise resides within professionals who are by definition autonomous. Where does the concept of autonomy in continuing professional development fit into the concept of workforce development? Tiered models for workforce and their development imply a final common path in career development, even in an area as multidisciplinary as public health. If this is so, do public health nutritionists need further formal qualifications, perhaps to become Masters of Public Health? Is this comparable to academic leadership in research conferred by a PhD in Public Health Nutrition? These questions illustrate the conceptual paradox surrounding the assumption that expertise is essentially hierarchical. This is arguably not the case. In Britain the discourse of public health practice has been facilitated by using a new conceptual model for the practice of public health (www.skillsforhealthuk.org). This model depicts a flower in which the petals represent discrete autonomous specialisms that contribute to the practice of public health (public health nutrition, midwifery, community nursing, health promotion, environmental health, etc). Simultaneously, each profession may be more or less strongly independent of the public health arena. In the model, the flower’s corolla depicts a core where some (generalists) exclusively practice public health. Or, the kind of collaborative multidisciplinary work we aspire towards and need is better conceptualised as a community of practice. Hughes makes an important theoretical contribution that is amenable to testing case studies in other countries than Australia, ideally prospectively, but also with existing data. For example, Warner built upon the Caribbean Food and Nutrition Institute’s published job descriptions for nutritionists and dietitians, supported by nutrition assistants and dietetic assistants, in turn supported by community health aides. Within a pyramidal model for workforce, qualifications determine seniority. Warner characterised the nutrition, dietetic and home economics workforce employed in public, private, and charity sectors in the English speaking Caribbean, to make recommendations on workforce planning and development. Warner’s approach may fit into Hughes’ conceptual framework, providing opportunities for adaptation and evaluation. Perhaps other case studies are possible with information arising from FAO Technical Support Programmes in the 60s and 70s. Dietetics serves as an entry-level qualification and is the primary professional socialisation in the life histories of many key informants in Australian public health nutrition who participated in Hughes’ research. This is reported in Hughes’ paper ‘Public health nutrition workforce composition, core functions competencies and capacity’. This link between dietetics and public health nutrition may be artifactual, due to the research setting, not necessary for professional development in public health nutrition. For example, between 1924 and 1944, before there was a Department of Nutrition at the London School of Hygiene and Tropical Medicine, officials in the Colonial Service were taught to undertake nutrition surveys, pari passu with the development of dietetics in Britain. In the postcolonial era, local education programmes