The bioavailability of vitamin C, or ascorbic acid, depends on limiting transport mechanisms that may be bypassed by liposome-encapsulation. The goal for this study was to evaluate the uptake, antioxidant, and immune-modulating effects of liposome-encapsulated vitamin C (LEC) using Lypo-Spheric® technology, compared to three controls: ascorbic acid (AA), the phospholipid fraction composing the liposome, and placebo. A double-blinded placebo-controlled cross-over study design involved twelve healthy participants attending four clinic visits. At each visit, a baseline blood draw was performed, followed by consumption of 1 g LEC, 1 g AA, the phospholipid component of LEC, or placebo. Additional blood draws were performed at 2, 4, and 6 h. Consuming LEC and AA increased blood levels of vitamin C; the levels were significantly higher after consuming LEC at all timepoints when compared to AA (p < 0.01). LEC consumption increased serum antioxidant capacity (p < 0.01 at 2 h) and protection. Consuming LEC increased IFN-γ levels at 6 h, while consuming the phospholipid fraction rapidly decreased inflammatory cytokines IL-6, MCP-1, and MIP-1α at 2 h. Consuming LEC provided enhanced vitamin C bioavailability and antioxidant protection compared to AA. Consuming the phospholipids had anti-inflammatory effects. The results suggest that LEC provides antioxidant and immune benefits above AA, useful in preventive medicine.
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