Natural C 1,000 mg tablets from DouglasLaboratories contain 1000 mg vitamin C with rosehips and an additional amount of bioflavonoidcomplex.Vitamin C (ascorbic acid) has numerous biologicalfunctions. Foremost, it is essential for the synthesis ofcollagen and glycosaminoglycans which are thebuilding materials of all connective tissues, such asskin, blood vessels, tendons, joint cartilage and bone.Vitamin C is the required coenzyme for two groups ofenzymes that catalyze the crosslinking of collagenfibers - lysyl hydroxylases and prolyl hydroxylases.As such, vitamin C is essential for normal woundhealing and capillary health. It also participates in thebiosynthesis of carnitine, serotonin, and certainneurotransmitters, including norepinephrine.Vitamin C is among the most powerful antioxidants inhumans and animals. It is a water-soluble, chainbreakingantioxidant that reacts directly withsuperoxide, hydroxyl radicals, and singlet oxygen.Laboratory studies show that vitamin C completelyprotects lipids in plasma and low-density lipoprotein(LDL) against atherogenic peroxidative damage. Inaddition, vitamin C interacts with glutathione andalpha-lipoic acid, and regenerates vitamin E. Theantioxidant functions of vitamin C appear to haveclinical significance in providing protection from freeradical damage to the eyes, lungs, blood and theimmune system.Vitamin C is absorbed in the small intestine by asodium-dependent transport process that is intakedependent. At normal dietary intakes of 60 to 100mg, up to 80 or 90% of the vitamin C is absorbed. Athigher intakes, absorption becomes less efficient.Absorption efficiency and vitamin C utilization maybe greatly enhanced during conditions ofphysiological stress, such as trauma or infection.Bioflavonoids (also called flavonoids) are a class of phytochemicals that are potent antioxidants, whichscavenge many potentially damaging free radicals.Another aspect of the antioxidant properties ofbioflavonoids is their synergy with vitamin C, a