Practical Nutrition Knowledge Mediates the Relationship Between Sociodemographic Characteristics and Diet Quality in Adults: A Cross-Sectional Analysis.

PURPOSE

To investigate the direct and indirect effects of sociodemographic/health factors on diet quality through practical nutrition knowledge (PNK) about how to compose a balanced meal.

DESIGN

A cross-sectional study using data from an online survey of the 10 000 Steps cohort (data collected November-December 2016).

SETTING

Australia.

PARTICIPANTS

Adults (n = 8161). Response rate was 16.7%.

MEASURES

Self-reported lifestyle, health, and sociodemographic characteristics, including diet quality and PNK.

ANALYSIS

The PROCESS macro for SPSS was used to conduct the mediation analyses.

RESULTS

Better diet quality was associated with being female, older, more highly educated, and having a lower body mass index. Mediation analysis showed that PNK significantly mediated the associations between sex (ab = 0.54, 95% confidence interval [CI] = 0.39-0.70) and education (vocational education: ab = 0.22, 95% CI = 0.12-0.35, university: ab = 0.48, 95% CI = 0.35-0.64), and diet quality. Practical nutrition knowledge suppressed the association between age and diet quality (ab = -0.03, 95% CI = -0.04 to -0.03).

CONCLUSION

Variations in diet quality between sociodemographic groups were partially explained by differences in PNK, suggesting that focusing public health efforts on increasing this specific knowledge type might be promising.