We would like to submit the following as a correction to our recently published paper. We calculated sodium-potassium ratios and compared them to an optimal sodium–potassium ratio recommended by WHO. The WHO optimal sodium–potassium ratio of 1.0 referred to in our paper is a molar ratio [1], whereas we have calculated the ratio (Table 2) using intakes expressed in mgs. There is some confusion in the literature on this issue, with some authors reporting the ratio using units of mg/day [2]. However, we accept that it is conventional, and therefore more useful from a public health standpoint, to report a molar ratio.
We include here a revised version of Table 2 that contains the sodium–potassium molar ratio. Interpretation of these results is largely the same, viz. that there is an unfavourable sodium–potassium ratio above 1 for all groups, rather than for all groups except women aged 45–64 years, which was demonstrated in the previous analysis. We would like to apologise for any confusion caused by this error in our paper.
Table 2.
The 24 h sodium, potassium and creatinine excretion: mean, standard deviation (sd) and 95% Confidence Interval (95% CI).
| Group | Sodium (mg/day) | Potassium (mg/day) * | Sodium:Potassium Molar Ratio * | Creatinine (mg/day) | |||
|---|---|---|---|---|---|---|---|
| Mean(sd) | 95% CI | Mean(sd) | 95% CI | Mean(sd) | 95% CI | ||
| Men: | |||||||
| 18–24 years | 3866 (1554) | 3405, 4327 | 2766 (813) | 2525, 3008 | 2.5 (1.1) | 2.2, 2.9 | 1706 (431) |
| 25–44 years | 3795 (1503) | 3372, 7217 | 3058 (957) | 2786, 3329 | 2.2 (0.8) | 2.0, 2.4 | 1703 (482) |
| 45–64 years | 3931 (1520) | 3517, 4347 | 3085 (1050) | 2798, 3371 | 2.3 (1.0) | 2.1, 2.6 | 1719 (401) |
| Total men | 3865 (1515) | 3618, 4113 | 2979 (955) | 2822, 3135 | 2.4 (1.0) | 2.2, 2.5 | 1710 (436) |
| Weighted mean † | 3854 | 3597, 4111 | 3005 | 2837, 3174 | 2.3 | 2.2, 2.4 | N/A |
| Women: | |||||||
| 18–24 years | 3017 (954) | 2724, 3311 | 2193 (632) | 1999, 2387 | 2.4 (0.8) | 2.2, 2.7 | 1174 (232) |
| 25–44 years | 3035 (1241) | 2706, 3365 | 2361 (839) | 2138, 2583 | 2.3 (0.9) | 2.1, 2.6 | 1188 (283) |
| 45–64 years | 2780 (1401) | 2418, 3142 | 2751 (784) | 2549, 2954 | 1.8 (0.7) | 1.6, 2.0 | 1100 (350) |
| Total women | 2934 (1235) | 2738, 3130 | 2463 (798) | 2337, 2590 | 2.1 (0.86) | 2.0, 2.3 | 1151 (299) |
| Weighted mean † | 2926 | 2716, 3137 | 2497 | 2363, 2631 | 2.1 | 2.0, 2.2 | N/A |
| Total men and women | 3386 (1452) | 3221, 3551 | 2712 (913) | 2608, 2816 | 2.2 (0.93) | 2.1, 2.3 | 1422 (465) |
* excluding one outlier with potassium excretion of 10,605 mg/day; † weighted to reflect age and sex structure of the New Zealand population aged 18–64 years in 2012.
Author Contributions
R.M. analyzed the data, all authors contributed to the text.
Conflicts of Interest
The authors declare no conflict of interest.
References
- World Health Organization. Guideline: Sodium Intake for Adults and Children; World Health Organization (WHO): Geneva, Switzerland, 2012. [Google Scholar]
- Drewnowski, A.; Maillot, M.; Rehm, C. Reducing the sodium-potassium ratio in the US diet: A challenge for public health. Am. J. Clin. Nutrition 2012, 96, 439–444. [Google Scholar]
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