Benefits of Vitamin C for Horses Vitamin C is an vital organic compound within a horse?s body; aiding in collagen production, iron absorption, hormone synthesis, bone calcification, regulation of antihistamine and supporting their immune system. Vitamin C is also a powerful antioxidant, helping to protect cells from damage. Unlike humans, horses can synthesize their own Vitamin C from glucose in their livers ? however deficiency can arise during period of stress or illness. A lack of Vitamin C can lead to several health problems in horses, including poor wound healing, reduced immunity, and joint pain. Sodium ascorbate is a more bioavailable form of Vitamin C, meaning that the body more easily absorbs it. As a result, supplementing with sodium ascorbate can help to ensure that horses get the Vitamin C they need to stay healthy.