L-Lysine is one of 9 essential amino acids that cannot be made in the body. It is the basic raw material for carnitine synthesis. L-Proline can be made in the body, but low-protein/vegetarian diets may not always promote optimal L-proline production. L-Lysine and L-proline amino acids are the precursors of hydroxylysine (HL), and hydroxyproline (HP), two constituents of collagen. Collagen is an essential component of arterial linings. Vitamin C, a strong antioxidant, is also essential for the production of collagen. Hawthorn berry and grape seed extract are potent natural antioxidants due to their high levels of proanthocyanidin. These proanthocyanidin-esters are excellent free radical scavengers.*