Distinct body fat distribution and its association with metabolic syndrome in Tibetan population

Objective To characterize the specific pattern of body fat distribution and its association with metabolic syndrome (MetS) among Tibetan adults, an understudied population with distinct high-altitude adaptations, and to identify potential mediating biomarkers in serum lipoprotein profiles. Methods A total of 1480 participants from the Tibetan cohort and the NHANES were included. Principal component analysis and Mantel tests were employed to identify Tibetan-specific body fat indicators. Linear models assessed associations with metabolic syndrome (MetS), and mediation analyses evaluated the indirect effects of serum lipoproteins. Results Tibetans showed distinct trunk and total fat mass compared to other ethnic/racial groups. Trunk fat percentage was identified as a risk factor for MetS (OR = 1.59, 95% CI: 1.27 ~ 1.91, p = 0.004). The triglycerides to total lipids ratio in low density lipoprotein 3 (L3TGP) and triglycerides to high density lipoprotein cholesterol ratio (TGHCR) exhibited significant mediating effect between trunk fat percentage and MetS (L3TGP:β = 1.7 × 10 − 4 g, 95% CI: 4 × 10 − 5 ~3.6 × 10 − 4 , p <0.001;TGHCR: β = 1.8 × 10 − 4 g, 95% CI: 4 × 10 − 5 ~4.6 × 10 − 4 , p <0.001). Conclusions This study revealed novel evidence for distinct fat distribution in Tibetans, linked to elevated MetS risk. L3TGp and TGHCR were identified as key lipoprotein mediators, supporting the need for environmental- and ethnicity-specific indicators in metabolic risk assessment.