Vitamin C (ascorbic acid) is a water-soluble vitamin that is essential to humans and must be obtained exogenously. While most mammals are able to synthesize vitamin C, humans are unable to. This is because humans lack one of the enzymes required to synthesize vitamin C from glucose. Stress, smoking, pollution, radiation and heavy metal exposure, immune challenge, and temperature change all increase the human requirement for vitamin C.
Well-known functions of this versatile vitamin include antioxidant protection from free radicals and oxidative processes; synthesis of collagen, carnitine, and neurotransmitters; and immune stimulation and support. Vitamin C functions as a cofactor for several metabolic enzymes and is involved in protein metabolism.
It also plays a lesser-known role in the deactivation of histamine. Collagen is a fundamental component of bone, tendons, ligaments, and blood vessels. Vitamin C’s role in collagen formation makes it vital to maintaining skin, capillary, gum, joint, and skeletal health. Vitamin C’s role in promoting and maintaining collagen, and consequently skin integrity, was recognized as early as the 1930s in published surgical journals.
Synthesis of carnitine depends on vitamin C, highlighting vitamin C’s role in energy production. Carnitine is the “car” that shuttles fatty acids into the mitochondria where they can be converted to the energy-yielding molecule adenosine triphosphate (ATP). Synthesis of certain hormones and neurotransmitters depends on vitamin C as well. It is required for the conversion of dopamine to norepinephrine—a neurotransmitter that is of great importance in maintaining healthy mood and brain function. Protecting tissues and organs from oxidative damage is believed to be pivotal in maintaining health in the body. Ascorbate, the reduced form of vitamin C (the form found in Xcellent C™), is a generous donor of electrons, allowing it to counteract oxidative free radicals.
