Low-grade chronic inflammation linked to obesity can lead to alterations in biomarkers of iron status. The aim of this study was to investigate the primary determinant of serum iron levels among anthropometric measurements, body fat, and serum biomarkers of low-grade chronic inflammation in a group of adult individuals with severe obesity. We enrolled 114 individuals (84 females; 30 males) aged 40.96 ± 12.54 years. Weight and body mass index (BMI) were 121.20 ± 22.33 kg and 44.94 ± 7.29 kg/m2, respectively. Some 30% of individuals had class-II obesity (BMI ≥ 35 ≤ 39.9 kg/m2) and 70% had class-III obesity (BMI ≥ 40 kg/m2). A weak, albeit significant, inverse correlation was found between serum iron levels and c-reactive protein (CRP) (r = −0.259, p = 0.008), fibrinogen (r = −0.261, p = 0.006), BMI (r = −0.186, p = 0.04), waist circumference (WC) (r = −0.265, p = 0.004), and fat mass % (r = −0.285, p = 0.003). With multiple linear regression analysis including CRP, fibrinogen, BMI, WC, and fat mass % as independent variables and serum iron levels as dependent variable, WC was entered in the first step (p = 0.001), which was followed by fat mass % (p = 0.047) and CRP (p = 0.047). Grouping the individuals according to the interquartile range of BMI, WC, and fat mass % (Q1–Q4), the lowest serum iron levels were found in Q4 groups of WC and fat mass % (p = 0.02), while no significant differences were found between groups in BMI quartiles. In conclusion, in our study, population serum iron levels were inversely associated with BMI, visceral obesity, fat mass %, CRP, and fibrinogen, but WC was the major negative predictor of serum iron level. These results supported the fact that visceral distribution of body fat, more than obesity per se, was associated with low serum iron levels in adult individuals with severe obesity.

Visceral obesity is linked to the progression of fatty liver to nonalcoholic steatohepatitis (NASH). Cytokeratin-18 (CK18) epitopes M30 (CK18M30) and M65 (CK18M65) represent accurate markers for detecting NASH. The aim of this study was to evaluate the association of CK18M30 and CK18M65 levels with anthropometric and metabolic characteristics, liver stiffness, and liver indices of steatosis and fibrosis in a cohort of subjects with visceral obesity; in this cross-sectional study, transient elastography (TE-Fibroscan®), anthropometric measurements, metabolic parameters, High Sensitivity C-Reactive Protein (hsCRP), and CK18M30 and CK18M65 levels (Apoptosense ELISA, PEVIVA, Germany) were evaluated. Fatty Liver Index (FLI), Fibrosis 4 (FIB-4), and Aspartate transaminase (AST)-platelet ratio index (APRI) were calculated; among 48 subjects, 47.2% presented metabolic syndrome, 93.8% hepatic steatosis, 60.4% high liver stiffness, and 14.6% hypertransminasemia, while FIB-4 and APRI were normal. CK18M30 and CK18M65 levels were significantly correlated with waist circumference, AST, ALT, HoMA-IR, liver stiffness, and APRI (p < 0.001). Subjects with CK18 fragments above the median values showed significantly higher waist circumference, HbA1c, AST, ALT, HoMA-IR, FLI, and APRI compared to those with values below the median; CK18M30 and CK18M65 levels correlated well with anthropometric and metabolic characteristics, representing good biomarkers for early identification of NASH in subjects with visceral obesity.