OBJECTIVES: Weight loss achieved by laparoscopic adjustable gastric banding (LAGB) induces an increase in high-density lipoprotein cholesterol (HDLc) but a small effect on low-density lipoprotein (LDL), although changes in their quality (size and composition) are uncertain. Our aim was to study the impact of weight loss, achieved 13-months after LAGB, on inflammation and dyslipidemia, focusing on HDL and LDL subfractions, and oxidized LDL (oxLDL). DESIGN & METHODS: We evaluated standard lipid profile, HDL and LDL subfractions, oxLDL, interleukin (IL)-6 and C-reactive protein (CRP), in twenty obese patients, before (T0) and 13-months after LAGB (T1), and in seventeen healthy controls. RESULTS: At T1, patients showed lower body weight (12% median weight loss) and anthropometric indices; reduction in TG, atherogenic indices, oxLDL, oxLDL/LDL ratio, CRP and IL-6, and enhancement in HDLc; an increase in large HDL and intermediate HDL subfractions, and a decrease in small HDL subfraction; LDL subfractions were not modified. Percentual change (%Δ) of oxLDL, from T0 to T1, correlated significantly and positively with %Δ of small HDL subfraction and with %Δ of body mass index. CONCLUSIONS: Weight loss induced atheroprotective changes on inflammation, and lipid profile, enhancing larger HDL, the more atheroprotective subfraction, reducing the less protective subclass, small HDL, and reducing oxLDL and oxLDL/LDL ratio. Quality of lipoproteins appears useful cardiovascular risk biomarkers, deserving further studies.