The association of schooling, sibling life situation, and dietary habits with the estimated 24-h urinary salt excretion and sodium-to-potassium ratio in 3-year-old children.

Objectives: We examined the association of schooling, sibling life situation, and dietary habits with the estimated 24-h urinary salt excretion and the urinary sodium-to-potassium (Na/K) ratio in 3-year-old children.

Methods: The subjects were 639 children who underwent a health checkup in four cities and towns in Kyoto Prefecture from January to November 2019. The children's parents answered questionnaires about weekday childcare places, the birth order, and the awareness of reducing the salt intake.