The SONG (Salt intake and OrigiN from General foods) Study - A Large-scale Survey of the Eating Habits and Dietary Salt Intake in the Working-age Population

OBJECTIVE: Dietary salt reduction is important for the prevention and treatment of lifestyle-related diseases, including hypertension. Thus, in order to follow a strict low-salt diet, it is necessary to assess one's salt intake and to become aware of the importance of salt reduction. METHODS: More than 2,000 employees of a company, who received a periodic health checkup, participated in the present study. They assessed their day-to-day diet-related lifestyle, using the Salt Check Sheet, and we analyzed the correlations among the Salt Check Sheet scores, the daily salt intake (as estimated by a spot urine sample), and the results of the periodic health checkup. RESULTS: In the overall survey population, we only found a weak correlation between the salt check scores and the salt intake. In a subgroup analysis, significant correlations between these two variables were observed among untreated hypertensive participants, but not among treated hypertensive participants. We examined the association between 13 individual questionnaire items and the estimated daily salt intake using a multivariate linear regression model and found that only 5 of the 13 questionnaire items were correlated with the daily salt intake. CONCLUSION: We found that a Salt Check Sheet composed of the 5 items that showed a strong correlation with the salt intake might be more useful for periodic health checks of the working-age population.