Exploring inflammation and adipose tissue dysfunction in metabolically healthy versus unhealthy obesity among Arab adults.

backgroundObesity is a heterogeneous condition. While Metabolically Healthy Obesity (MHO) is often considered to carry a lower risk of metabolic complications than Metabolically Unhealthy Obesity (MUO), findings on their differences remain inconsistent. This study examines for the first time the metabolic differences across obesity phenotypes in Saudi adults, addressing a literature gap in understudied populations with high obesity prevalence. MATERIALS AND

methodsThis cross-sectional study included 450 Saudi adults classified as MHO, MUO, or metabolically healthy normal weight (MHNW) based on BMI (≥ 30 kg/m²) and the presence of ≥ 3 metabolic abnormalities per National Cholesterol Education Program (NCEP) criteria. Anthropometric, metabolic, and inflammatory parameters were assessed. Age- and sex-adjusted logistic regression analyses were used to compare phenotypes.

resultsMUO individuals showed significantly higher adiposity indices, insulin resistance (HOMA-IR), and inflammatory markers compared to MHO individuals (p-values < 0.001). MHO individuals also differed significantly from MHNW individuals. Adiponectin levels were comparable across groups; however, the Adiponectin/Leptin ratio (adpn/lep) was lowest in the MUO group, indicating adipose tissue dysfunction. MUO individuals had increased odds of elevated HOMA-IR (OR = 5.76, p < 0.001) and CRP (OR = 2.64, p = 0.005) compared to MHO. While insulin resistance did not differ significantly between MHO and MHNW, MHO participants had higher odds of a low adpn/lep ratio (OR = 2.87, p < 0.005).

conclusionMUO individuals exhibited greater metabolic risk than MHO, with marked insulin resistance and inflammation. However, the presence of adipokine imbalance and elevated inflammatory markers in MHO suggests that ‘metabolic health’ in obesity may be relative rather than absolute.