BRIEF RESEARCH REPORT article

Front. Nutr.

Sec. Nutritional Epidemiology

Volume 12 - 2025 | doi: 10.3389/fnut.2025.1613685

Dietary soy and isoflavone intake and mortality in Korean adults: a prospective cohort study

Provisionally accepted
Sihan  SongSihan Song1,2Shinyoung  JunShinyoung Jun3Hyojee  JoungHyojee Joung1Jung Eun  LeeJung Eun Lee1*
  • 1Seoul National University, Seoul, Republic of Korea
  • 2Korea National Institute of Health, Cheongju-si, Republic of Korea
  • 3Soonchunhyang University, Asan, South Chungcheong, Republic of Korea

The final, formatted version of the article will be published soon.

Background: The association between dietary soy and isoflavone intake and mortality remains inconclusive. This study aimed to examine the relationships of dietary intakes of isoflavones, soy protein, and soy foods with all-cause, cancer, and cardiovascular disease (CVD) mortality in Korean adults.Methods: This prospective cohort study included 118,450 Korean adults aged 40–79 years from the Health Examinees Study (2004–2013). Dietary intakes of isoflavones, soy protein, and soy foods were assessed using a food frequency questionnaire. Cox proportional hazards models were used to estimate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for mortality risk according to quartiles of dietary soy and isoflavone intake.Results: During a median follow-up of 10.1 years (interquartile range: 8.7–11.4 years), 2,614 deaths were documented, including 1,290 from cancer and 389 from CVD. Multivariable analyses showed no significant associations between dietary isoflavone intake and the risk of all-cause and cause-specific mortality. The HRs (95% CIs) comparing the highest vs. the lowest quartile of isoflavone intake were 1.04 (0.93–1.15) for all-cause mortality, 0.98 (0.84–1.14) for cancer mortality, and 1.04 (0.79–1.38) for CVD mortality. Similarly, no significant associations were observed for soy protein or soy food intake in relation to all-cause, cancer, and CVD mortality.Conclusion: Our study found no significant associations of dietary intakes of isoflavones, soy protein, and soy foods with the risks of all-cause, cancer, and CVD mortality.

Keywords: Isoflavones, Soy Foods, Mortality, Cancer, cardiovascular disease

Received: 17 Apr 2025; Accepted: 13 Jun 2025.

Copyright: © 2025 Song, Jun, Joung and Lee. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

* Correspondence: Jung Eun Lee, Seoul National University, Seoul, Republic of Korea

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