Distinct Body Fat Distribution and Its Association with Metabolic Syndrome in Tibetan Population

Objective: Although ethnic/racial differences in body fat distribution have been documented, the specific pattern in Tibetans and its implications for metabolic health in this high-altitude population remain unclear. 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). 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 x 10 ^-4 g, 95% CI: 4 x 10 ^-5 ~3.6 x 10 ^-4 ;TGHCR: β = 1.8 x 10 ^-4 g, 95% CI: 4 x 10 ^-5 ~4.6 x 10 ^-4 ). 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.