Evaluation on association between urinary sodium/potassium ratio and daily sodium intake utilizing international collaborative epidemiological research data

2022 Fiscal Year Final Research Report

• Project/Area Number: 18K17377
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 58030:Hygiene and public health-related: excluding laboratory approach
• Research Institution: Shiga University of Medical Science
• Principal Investigator: Iwahori Toshiyuki 滋賀医科大学, 医学部, 客員准教授 (80750249)
• Project Period (FY): 2018-04-01 – 2023-03-31
• Keywords: 栄養疫学 / 高血圧 / 塩分摂取 / カリウム摂取 / ナトリウムカリウム比

Outline of Final Research Achievements

Excess sodium (Na) intake is a major factor of lifestyle related disease such as hypertension and stroke; it has yet been solved in Japan. Urinary Na/K ratio is much easier to measure dietary habit of individuals compared to conventional dietary sodium; however, the corresponding value of urinary Na/K ratio to sodium intake remained unknown. This study clarified that urinary Na/K ratio less than 2 will be a reasonable value for maintaining healthy dietary habit for preventing cardiovascular disease by referencing the conventional dietary sodium intake values. The study result will be useful for guiding citizens to ideal healthy diet by self-monitoring their daily dietary habit.

Free Research Field

疫学

Academic Significance and Societal Importance of the Research Achievements

尿Na/K比の測定は塩分摂取量の測定よりも簡便で、かつgold standardとなる24時間蓄尿により推定される値に対しても複数回測定することで信頼性が高いことが報告されている。本研究の結果により、塩分摂取量のWHOや学会推奨値に対する尿Na/K比の対応関係が明らかになった。これまで闇雲に食生活の改善に取り組むケースが多かったが、個人の食生活の状況を把握できるセルフモニタリング機器の開発が尿Na/K比では可能である点を踏まえると、循環器疾患の予防のための理想的な食生活に向けた努力を個人個人で実施できる基盤整備に直結する成果であったと考えられる。