Background/Aims: To assess sodium and potassium intake in New Zealand adults using 24 hour urine samples.
Methods: A random sample of New Zealand Adults aged 18 to 64 years was selected from the electoral roll in two cities: Dunedin and Wellington. Participants completed a questionnaire with sociodemograhic information, had height, weight and blood pressure measured, and provided a 24h urine sample, which was analysed for sodium and potassium content.
Results: Mean sodium:potassium ratio was 1.32 (95%CI 1.26, 1.39); 1.39 for men and 1.26 for women. Mean 24 hour sodium excretion was 3386mg/day (95%CI 3221, 3551): 3865 mg/day for men and for 2934 mg/day women. Mean 24 hour potassium excretion was 2738mg/day (95%CI 2623, 2855): 3031mg/day for men and 2436 mg/day for women. Sodium intake was higher among younger people, men, those with a higher BMI and higher potassium excretion. Potassium excretion was higher among older people, men and those with a higher sodium excretion.
Conclusions: New Zealand adults have high sodium intakes and low potassium intakes compared to recommended levels. Dietary sodium intakes have remained relatively stable since the late 1970s. A comprehensive public health programme to reduce dietary sodium intake and increase intake of fruit and vegetables would help reduce population blood pressure and incidence of cardiovascular disease.
Funding source: Ministry for Primary Industries of the New Zealand government.