Since 1947 Antioxidant Support Immune System Non-GMO Certified Gluten Free, Wheat & Dairy Free Kosher Parve Suitable for Vegans Dietary SupplementVitamin C is a water-soluble vitamin that helps fight free radicals, which can lead to oxidative stress and the premature aging of cells. One of its primary functions is collagen formation, which is important for healthy skin and joints. Vitamin C also plays an essential role in the functioning of white blood cells, which are vital components of the immune system.