Metadiscourse in open-access journal articles on the Mediterranean diet: A diachronic corpus-based study

This dissertation explores the use of metadiscourse in open-access journal articles focusing on the Mediterranean diet and its impact on health. It aims to investigate the question of how the authors of research articles choose to interact with the readers and if and to what extent their linguistic choices have changed over time. Although the phenomenon of metadiscourse has been studied in the context of diverse disciplines such as biology, astrophysics, marketing, applied linguistics and in genres including introductory textbooks, research articles and popularizations, no diachronic corpus-based study of metadiscourse in the field of nutrition science and the Mediterranean diet has been yet conducted. To address this gap, I created a corpus of 112 open-access research articles about MedDiet, written in English by authors from different countries and published in Plos One, BMC, ArXiv, American Journal of Nutrition and a number of other journals. The period in which the articles under scrutiny were published ranges from the 1980s and till the present day. By adapting Hyland’s interpersonal model of metadiscourse, interactive and interactional categories were identified and quantified with the help of AntConc corpus tool. A comparative analysis was performed by aligning metadiscourse markers per 1,000 words and comparing the results with the data presented by Hyland. Individual metadiscourse categories were examined both qualitatively and quantitatively across time. The findings show the consistent use of metadiscourse in the Mediterranean diet research articles over time. Some frequencies slightly decreased in certain periods but remained almost equal when the earliest and the latest decades are compared. However, interactional markers usually prevail in each sub-corpus, demonstrating the writers’ increased use of hedges among all other categories. This suggests that authors in this field opt for setting a cautious voice, indicating relative uncertainty and leaving a space for further negotiations of claims. Thus, the dissertation contributes to research on metadiscourse as it discusses a diachronic, discipline-specific case study and offers potential applications for academic writing in nutrition, medicine and related sciences.