Purpose: We sought to estimate the proportion of the Japanese sexual and gender minority (SGM) population, and to describe those demographic, socioeconomic, and health-related variables. Materials and Methods: Utilizing data on a nationwide cross-sectional internet survey from September 12th to October 19th, 2022, we conducted a comprehensive descriptive study by applying inverse probable weighting method for nationally representativeness. Participants self-reported as heterosexual, homosexual, bisexual, or gender minority (GM) and responded to questions on various aspects, including demographic, socioeconomic, and health-related concerns. Results: Among Japanese adults, 4.8% identified as homosexuals, 1.3% as bisexuals, and 3.8% as GMs. While SGMs were less likely to be married/partnered compared to heterosexuals, a certain proportion of SGMs were opposite-sex married/partnered. All or some categories of SGM had a lower proportion of household equivalent income, insurance coverage, owing house, current smoker, good self-rated health, and fully COVID-19 vaccination; and a higher proportion of substance users, severe psychological distress, feeling loneliness, and Fear of COVID-19, compared to heterosexuals. When divided by assigned sex at birth, compared to heterosexual counterparts, SGM males had poorer employment status, lower academic attainment, and higher body mass index, while females showed the opposite association. Conclusion: We clarified differences in demographic, socioeconomic, and health status between heterosexuals and SGMs, which partially differ from those in previous Western studies. These results emphasize the need for health policies and interventions to address health disparities in Japanese SGM. They also imply that generalizing Western policies to Japan may not always be practical.

The authors have declared no competing interest.

the Japan Society for the Promotion of Science, the Research Support Program to Apply the Wisdom of the University to tackle COVID-19 Related Emergency Problems, University of Tsukuba, and Health Labour Sciences Research Grantand the Japan Agency for Medical Research and Development.

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The research ethics committees of the Osaka International Cancer Institute and National Cancer Center approved the study protocol (approval number: 20084 and 2020-447, respectively).

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