METHODS: Baseline and 1-year follow-up data from 5800 participants in the PREDIMED-Plus study were used. Each participant's food intake was estimated using validated semi-quantitative food frequency questionnaires, and the adherence to MD using the Dietary Score. The influence of diet on environmental impact was assessed through the EAT-Lancet Commission tables. The influence of diet on environmental impact was assessed through the EAT-Lancet Commission tables. The association between MD adherence and its environmental impact was calculated using adjusted multivariate linear regression models.
RESULTS: After one year of intervention, the kcal/day consumed was significantly reduced (-125,1 kcal/day), adherence to a MD pattern was improved (+0,9) and the environmental impact due to the diet was significantly reduced (GHG: -361 g/CO2-eq; Acidification:-11,5 g SO2-eq; Eutrophication:-4,7 g PO4-eq; Energy use:-842,7 kJ; and Land use:-2,2 m2). Higher adherence to MD (high vs. low) was significantly associated with lower environmental impact both at baseline and one year follow-up. Meat products had the greatest environmental impact in all the factors analysed, both at baseline and at one-year follow-up, in spite of the reduction observed in their consumption.
CONCLUSIONS: A program promoting a MD, after one year of intervention, significantly reduced the environmental impact in all the factors analysed. Meat products had the greatest environmental impact in all the dimensions analysed.
KEY FINDINGS: Research philosophy has been introduced to offer an alternative way to think about problem-driven research that is normally conducted. To clarify the research philosophy, four research paradigms, i.e. positivism (or empiricism), postpositivism (or realism), interpretivism (or constructivism) and pragmatism, are investigated according to philosophical realms, i.e. ontology, epistemology, axiology and logic of inquiry. With the application of research philosophy, some examples of quantitative and qualitative research were elaborated along with the conventional research approach. Understanding research philosophy is crucial for pharmacy researchers and pharmacists, as it underpins the choice of methodology and data collection.
CONCLUSIONS: The review provides the overview of research philosophy and its application in pharmacy practice research. Further discussion on this vital issue is warranted to help generate quality evidence for pharmacy practice.