The science and art of dietetics: Why science needs to underpin our practice

Dietetics is often described both as an art and a science;1-3 a science as it is derived from the science of nutrition and an art because of the translation of the science by practitioners into practice. The science of nutrition—the interaction of nutrients and other substances in food in relation to growth and health—draws from the foundational sciences of chemistry, biology, microbiology, physiology and biochemistry. Importantly, the science of food, the study of the chemical and physical properties of food and how composition may change with different levels of processing, is the conjugate of how nutrition is translated into dietetic practice. Each of these three pillars—nutrition, food and dietetics—are underpinned by science and this needs to be continually supported in practice. Here, the observation of a problem leads to the formation of a hypothesis. This hypothesis is then tested by conducting a fair and unbiased experiment, the data are analysed and a conclusion drawn—the whole process evaluated by submission of a manuscript for peer review. Dietitians are in a unique position to identify gaps in knowledge from their practice, to develop hypotheses and then collect and analyse the data and determine how they are translated into practice. Adherence to the scientific process and the use of well-developed and validated scientific methodologies is required to develop the evidence base that will help dietitians to continually improve the health of future generations and is critical in retaining the profession's credibility. Papers themed in this issue of Nutrition & Dietetics reflect the diversity of the different methodologies used to test their hypotheses within nutrition research, without the requirement for time intensive and costly traditional intervention studies such as randomised controlled trials (RCTs). These include systematic reviews,4 and qualitative methodologies such as online surveys5 and focus groups6 to monitor and assess efficacy. Also in this issue researchers have utilised existing RCTs to analyse secondary data,7 and report longitudinal observational studies8-10 to address existing gaps in the knowledge base in clinical dietetics. A systematic review is a powerful research methodology that provides a structured framework to collect and analyse data from multiple studies, which provides high-level evidence to inform health-care practice. The nutritional intakes of children continue to be a strong research focus, especially given the long-standing understanding of the trajectory of poor diets in childhood and childhood obesity leading to an increased risk of poor metabolic outcomes in adulthood.11 With the awareness that grandparents are increasingly involved in the care of their grandchildren, the systematic review by Young et al. addresses a potentially important aspect of determinants of children's dietary intakes.4 Studies where grandparents provided care to 2–12-year-olds were considered, excluding where grandparents were primary caregivers and studies from developing countries. Studies were eligible for inclusion if they had reported outcomes on the children's dietary intake and weight, and the grandparent's knowledge and beliefs on nutrition or their feeding practices. Three studies were identified in which grandparents had positive feeding behaviours towards their grandchildren, while nine studies identified that grandparents had negative impact on feeding attitudes and behaviours. Many of these included studies also reported qualitative data, providing a rich understanding of the influences and reasons behind their beliefs. Influences ranged from the negative in which grandparents actively undermine the parents—to the positive in which parents and grandparents worked together to ensure that traditional family recipes were passed down the younger generations. Importantly, this review of the evidence base highlights grandparental influence as another potential determinant of childhood obesity. Monitoring nutritional status in health care has always been at the forefront of clinical dietetic practice. Aredes et al. addressed the critical question of how chemotherapy and radiotherapy affect nutritional status during therapy, specifically in the under-studied area of gynaecological cancer. A longitudinal prospective cohort study design was used to assess the influence of chemotherapy on the nutritional status, functional capacity and quality of life in women receiving treatment for cervical cancer in the National Institute of Cancer in Jose Alencar Gomes da Silva.10 One of the clinically significant findings of this manuscript was that the interruption of chemotherapy due to severe toxicity (either due to gastrointestinal, haematological or renal toxicity) was significantly associated with nutritional status prior to the commencement of chemotherapy. The cohort (20.4%) that suspended their chemotherapy had a significantly lower median skeletal muscle index. Furthermore, in the cohort that had treatment suspended, 83% had presented prior to treatment with cachexia and unintentional weight loss of more than 5%. It has been proposed that percentage weight loss is a better clinical indicator rather than body mass index in patients undergoing chemotherapy as a prognostic factor of quality of life, regardless of the type of cancer.12 This is an important consideration for clinical dietitians in ensuring weight maintenance (including fat-free mass) prior to chemotherapy treatment, forming part of the evidence base that will be incorporated into clinical practice. The impact of and adherence to clinical practice guidelines in dietetic practice was also investigated in this issue by Bourne et al. Australian dietitians working with bariatric patients were surveyed for their adherence to the clinical practice guidelines for the nutritional, metabolic and non-surgical management of bariatric surgery patients in the pre-operative stage.5 This research employed a descriptive cross-sectional online survey to assess adherence to clinical practice guidelines.13 The proportion of dietitians reporting routine screening of at-risk micronutrients varied between 32 and 45% in the regional and remote areas, whilst in the metropolitan areas there was a higher proportion of screening with reports between 55 and 65%. This study demonstrates that all dietitians implemented some form of medical nutrition therapy to facilitate weight loss pre-operatively, but highlights the need of continued research into this area to determine the barriers to nutrient screening. As reflected in the diversity of papers in this issue, dietitians practice in many different areas, and need to continually draw on the foundational sciences and the evidence base so that they can advocate, promote and provide the highest quality care, advice and education for our clients and community. Our ultimate goal has always been to improve the health of future generations, requiring continual professional development, remaining abreast of the literature and translating the evidence base into practice for the future generations. Yet arguably, the biggest challenge for those practising as dietetic and nutrition professionals may be to prove that nutrition is not a belief system, but a science. The ‘art of dietetics’ has also become somewhat more difficult due to the growing number of ‘health practitioners’ who are providing ‘nutritional’ advice and who have mastered the ‘art’ of nutrition, without mastering the science that underpins it.14 Clearly their success has been facilitated by the widespread prevalence of social media,15 where everybody has a voice. This makes it a difficult space for the dietitians’ voice to compete, especially when the public perception is that nutrition is not science-based, but rather where the authenticity of the message is linked to the familiarity and popularity of the celebrities sprouting their message,16, 17 often driven by significant conflicts of financial interest. This phenomenon continues to be fuelled by ‘hash-tag pop science’ terms such as ‘clean eating’, ‘detoxing’, ‘freedom’, ‘natural’ and ‘superfood’. This situation is perhaps further exacerbated with health professionals at the face of delivering health care who could provide basic nutrition knowledge but receive poor nutrition training, which denies them the foundational understanding that nutrition is a science.18, 19 The ‘art of dietetics’ should be more widely viewed as, perhaps, how dietitians communicate that nutrition is a science when advocating their message to improve the health of future generations. This highlights the importance for dietitians to have scientific literacy so that they understand the research process, including the strengths and limitations of different methodologies. This requires dietitians to become engaged in research in nutrition, food and dietetics. The dietitians’ voice is particularly important in food science principally because of their knowledge of nutrients, food components and the impact that changes in the food industry are likely to have in health and disease. So, let us remember the quote from John Cleese “science—a method of investigation and not a belief system”.20 Dietetics is a science, in which dietitians with enquiring minds need to use and understand the methods of investigation with a non-biased mind to avoid investigator bias. To enable this scientific process, high level scientific literacy is required which needs to be heavily emphasised in undergraduate and post-graduate degrees, and in professional development. Adhering to these are critical for dietitians to maintain their credibility in the many areas that they practice in, from research, education, industry and of course all levels of health care to achieve their goal of improving nutritional status for people for better health outcomes. The author did not receive funding to write this Editorial. The author has no conflicts of interest to declare. EM was the sole author of this manuscript.