This study developed a Japanese version of the Body Appreciation Scale-2 (BAS-2), a measure for a comprehensive assessment of positive body image, and investigated its reliability and validity. The results of confirmatory factor analysis showed that, like the original version, the Japanese BAS-2 had a one-factor structure and invariance across gender. Body appreciation scores had good internal consistency, test-retest reliability, and construct validity. Furthermore, the scale exhibited incremental validity by predicting psychological elements (disordered eating, self-esteem, and satisfaction with life) above and beyond body dissatisfaction. Thus, the BAS-2 is suitable for the assessment of positive body image in the Japanese population.

Background: Body image research deals a lot with awareness of the body as an entity. Studies that consider individual anatomical aspects and place them in an intercultural context are rarely present. Methods: For this purpose, general data, body perception and judgment of body images from 2163 (48% female and 52% male) participants from Germany, Nigeria, the USA and Japan were evaluated as part of a survey. Results: There were clear differences in the personal body image of the participants’ own buttocks, the buttocks as a beauty ideal and the way in which dissatisfaction was dealt with in different countries. In addition to sexual well-being (importance score: 0.405 a.u.), the country of origin (0.353), media consumption (0.042) and one’s own weight (0.069) were also identified as influencing factors for satisfaction with one’s own buttocks. A clear evolution could be derived regarding a WHR (waist-to-hip ratio) of well below 0.7, which was consistently favored by the participants but also propagated by influencers through images (p < 0.001). In this context, participants who indicated celebrities as role models for the buttocks showed a correspondingly high level of dissatisfaction with their own buttocks (R = −0.207, p < 0.001, ρ = −0.218). Conclusion: Overall, a highly significant correlation was shown between the consumption frequency of Instagram, TikTok and pornography with the negative perception of women’s own buttocks.