Oxidative stress and antioxidant deficiency are contributing factors in aging, cardiovascular disease, diabetes and cancer. The effect of highly bioavailable polyphenols of lycosome-formulated dark chocolate (DC) containing co-crystallized astaxanthin (LF-DC-ASTX) on parameters of biological oxidation was investigated in this work. 94 healthy middle-aged volunteers (48 male, 46 female, 45 -65 years old) were enrolled and randomized into four study groups. The 1 st group were instructed to ingest conventional control DC (7.5 g). The 2 nd group were asked to ingest capsules containing either 4 mg or 7 mg astaxanthin (ASTX), an algal antioxidant. The 3 rd group were given DC bars (7.5 g) and 4 mg ASTX capsules for co-ingestion as two separate formulations. The 4 th group were instructed to ingest LF-DC-ASTX containing different amounts of ASTX (1 mg, 2 mg, 4 mg or 7 mg) cocrystallized with 7.5 g of DC matrix. Each product was ingested once daily after breakfast for a period of 1 month. Serum levels of oxidized LDL (ox-LDL) and malonic dialdehyde (MDA) were measured after completion of 2 and 4 weeks of the study. No significant changes were observed in the values for ox-LDL or MDA concentrations in serum irrespective of cocoa content (70%, 72% or 85%) or duration of control DC intake. In contrast, ingestion of different doses of ASTX, as a single formulation, translated into reduction of oxidation markers without any dosedependency. The inhibition of ox-LDL in volunteers following co-ingestion of DC and ASTX as two separate formulations was far greater than that seen for ASTX alone, revealing some additive effect of DC on lipid oxidation parameters. The inhibition of both oxidative markers was dose-dependent reflecting amount of ASTX in the DC matrix. These results may reflect greater bioavailability and improved pharmacokinetics for cocoa flavanols and ASTX following ingestion of LF-DC-ASTX. Therefore, nutraceutical formulations of DC fortified with ASTX can be successfully used for management of oxidative disorders associated with increased levels of ox-LDL.