NOW&ampreg; AlphaSorb-C&ampreg; includes Transport C-PLUS&ampreg;, the trademarked blend of Threonic Acid Enhanced Buffered (non-acidic) Calcium Ascorbate and Alpha Lipoic Acid. Threonic Acid (a Vitamin C metabolite) has been shown to enhance cellular uptake of Vitamin C. Alpha Lipoic Acid is an antioxidant known to help regenerate Vitamin C in the body. Furthermore, studies suggest that Alpha Lipoic Acid may enhance the body's utilization of Vitamin C. The addition of Bioflavonoids helps to create a well-absorbed, highly effective Vitamin C supplement. Vitamin C is best known as a highly effective antioxidant that can protect the body's cells and molecules from damage by free radicals.*