Sleep disorders affect a large population, with demand for sleep support on the rise. Although previous research has explored the relationship between specific nutrients and insomnia, comprehensive analyses of daily eating patterns of macro- and micronutrients remain limited.

Diets high in sodium, low in potassium, or both, have been associated with altered nocturnal blood pressure decrease (when blood pressure does not decline as much as it normally does at night).

At the same time, nocturnal hypertension has been linked to sleep disturbances.

As such, a cross-sectional study in Japan examined the relationship between potassium and sodium intake and insomnia among healthy Japanese adults.

Dietary data on energy intake and consumption of protein, fat, carbohydrates, sodium, and potassium during breakfast, lunch, dinner, and snacks spanning January to February 2021 were derived from Asken, a widely used Japanese food-logging mobile app.

Users can input ingredients, dishes, and portion sizes into the app, which automatically calculates calorie and nutritional intake by referencing the Standard Tables of Food Composition in Japan, 2020 (Eighth Revised Edition), as determined by the country’s Ministry of Education, Culture, Sports, Science and Technology.

The app boasts over 11.2m downloads as of November 2024. Self-reported food records accumulated on the app have been validated as reliable for research purposes.

As part of the study, online survey responses were obtained from 4,568 app users (3,320 women and 1,248 men) a