Purpose <p>Immigrant populations face heightened risk of metabolic disorders due to dietary transitions, socioeconomic vulnerability, and cultural practices. This study assessed sex-specific differences in metabolic biomarkers among immigrants in Greece and examined associations with dietary patterns and lifestyle factors.</p> Materials and methods <p>In a cross-sectional study, 393 adult immigrants (211 men, 182 women) provided blood samples and completed structured dietary and lifestyle questionnaires. Biochemical analyses included glycemic, lipid, hepatic, renal, micronutrient, and inflammatory markers. Dietary intake was assessed with a frequency questionnaire, validated against biomarkers, and analyzed using principal component analysis (PCA). Associations were tested with correlation and multivariable regression models.</p> Results <p>Women exhibited significantly lower serum vitamin D (<i>p</i> &lt; 0.001) and ferritin (<i>p</i> = 0.002) and higher prevalence of hypoalbuminemia, vitamin B12 deficiency, and elevated HbA1c, whereas men had higher triglycerides, creatinine, and ferritin. Strong positive correlations were observed between alkaline phosphatase and creatinine (rs = 0.723, <i>p</i> &lt; 0.001), and between SGOT-AST and albumin (rs = 0.737, <i>p</i> &lt; 0.001). The PCA-derived Processed/Western dietary pattern was positively associated with C-reactive protein (β = 0.051, <i>p</i> = 0.041). Fish intake showed a borderline positive association with vitamin D (β = 0.063, <i>p</i> = 0.094). Smoking and alcohol were more prevalent among men, while physical activity did not differ by sex.</p> Conclusions <p>Immigrant metabolic health is shaped by the intersection of diet, lifestyle, and sex-specific vulnerabilities. High rates of nutrient deficiencies and metabolic dysregulation highlight the need for culturally tailored preventive strategies and biomarker-informed dietary interventions.</p>