Comparison of salt reduction policies and trends levels in dietary salt intake in Japan and other countries: A narrative review

Abstract

Objectives　This study compared salt reduction policies and trends in dietary salt intake between Japan and other countries to facilitate future implementation of salt reduction initiatives in Japan.

Methods　Information on salt reduction policies, salt intake, and target values in G7 member countries (Japan, the United States, Canada, the United Kingdom, Italy, France, and Germany) and countries with similar food cultures (China and Korea) since 2000 has been collected from institutional, article, and report websites. If sodium data were available for a specific country (the United States, Canada, or Korea), the sodium value and the salt equivalent value, calculated by multiplying the sodium value by 2.54, were presented. The percentage reduction was calculated from the baseline and assessment values of salt reduction policies in Japan and the United States. In other countries, it was calculated from near-year values before and after the salt reduction policy because these countries did not confirm the baseline and assessment values.

Results　All the target countries set target values for dietary sodium or salt intake. The salt equivalents of the target values ranged from 5.8 g/day (Canada) to 9.9 g/day (Korea). In the United Kingdom, Italy, and France, some food industries, such as bread and pasta, have entered a pact to limit sodium. Korea has been implementing a salt reduction approach, not only in the food industry but also at home, such as the development of salt reduction menus. The main sources of dietary sodium in the United States, Canada, the United Kingdom, Italy, France, and Germany are processed and cooked foods, whereas in Japan, China, and Korea, sodium is consumed at home from condiments. Although the current salt intake could not be compared because of differences in the approach and years studied, it ranged from 6.9 g/day (Canada) to 10.2 g/day (China). Salt intake showed a decreasing trend in all countries, especially Korea and the United Kingdom, with particularly large reductions (32.2% and 14.8%, respectively). The United States and Japan showed lower reductions than other countries (2.2% and 4.7%, respectively).

Conclusion　This study revealed that the percentage reduction in salt intake among the Japanese population was lower than that in other countries, highlighting the need for a tailored approach to salt reduction policies in Japan.