Limitations and strengths
There were some limitations to this study. First, it was challenging to perform double-blinding (blinding of the interventionist and participants) due to the nature of the study. Although we maintained continuous social contact with the control group to avoid the confounding effects of psychosocial contact, it was not possible to compensate entirely for the Hawthorne effect. Second, the method of assessing food intake in this study might have led to bias in estimating the amount of food that was consumed. Because the participants self-reported the amount of their food intake, there might have been variations between the actual amount and the estimated amount, even though the participants had been trained in measurement methods. However, the food diary is the most widely used method in current dietary intervention studies especially in a community-dwelling setting. We also considered using digital methods (e.g., technological equipment or application programs) to help in recording food intake. However, the accuracy of digital methods is yet to be established, and the problems of self-reporting remain unsolved [This study has implications for both clinical practice and research. First, this study provides a good reference for community health providers to use to play a supervisory role in implementing dietary interventions using behaviour change techniques (e.g., workshops or telephone follow-ups), and then to improve the quality of the diets of older adults. Notably, the intervention in this study used an individualised rather than a uniform approach, which is crucial for dietary interventions considering the heterogeneity among participants in terms of lifestyle, mealtimes, confidence, and family context. Second, this study inspired the design for future research, i.e., a longer intervention duration and better-tailored methods for promoting compliance in the keeping of a food diary. In this pilot study, handgrip strength, waist-hip ratio, and gait speed all showed a non-significant positive change. Supposing these parameters could be significantly changed in a longer intervention duration and a bigger sample size.