There are many factors that affect vitamin D supplementation, including those from the theory of planned behaviour (TPB); however, how the perceived benefit acts in the model remains unknown. In the current study, we tested the efficacy of the TPB and the impacts of the perceived benefit (PBE) in the model. The subjects were 287 customers who purchased vitD from pharmacies in major cities in Taiwan. A structured questionnaire was used to collect the data. t-tests, analysis of variance (ANOVA), regression analyses, and path analysis via SPSS and AMOS were used to analyse the data. The original TPB model explained 47.5% of the variance of intention with the three variables of attitude (β = 0.261), perceived behavioural control (β = 0.183), and subjective norms (β = 0.169). The model that incorporated PBE increased the explained variance to 59.7%, and PBE became the strongest predictor (β = 0.310) and a significant mediator linking attitude, subjective norms, perceived control (ANC) with supplementation intention. PBE and attitude were the two most important variables in predicting vitD supplementation intention. We suggest that updated information regarding dietary sources of vitD and its benefits should be included in health- or nutrition-related courses in education programs for the overall health of the nation.

The charm of food photos plays a decisive role in advertising because people search and buy food on the Internet more frequently than ever. Photos with appealing food design elements can immediately attract people's attention. The same food with different design features will attract different consumer groups through photos on the web. They greatly affected consumers' feel, and purchase decisions. This study uses Taiwanese mango ice as an example to explore the perceptual reasons why consumers are attracted to existing mango ice products, their attractive design features, and the relationship between the two. Miryoku engineering was used to explore the relationship between consumers and the appeal of food design revealed by photos, the Evaluation Grid Method (EGM) was used to extract the attractive factors of food design, and the Quantification Theory Type 1 (QTT1) is used to analyze the weight of each design feature that affects the charm of food. Three Kansei factors and 16 concrete design elements were obtained through EGM, and the weights of food design elements that influence the charm were found using QTT1. The results show that the obtained regression models can explain the relationship between the design elements of food photos and the perception of customers. The application have important reference value for evaluating food design elements and market segmentation of consumer groups. This research proves the feasibility of using Kansei engineering to explore the charm of food design, and has reference value for future related research.