Natural Factors Vitamin C Crystals - 1000 mg - Ideal for those who have difficulty swallowing pills - just mix in juice or shakes and get 1000 mg of pure Vitamin C in each 1/4 teaspoon serving. Vitamin C is a well-known, proven and powerful antioxidant, derived from diet or supplementation, essential for boosting immune functions, balancing cholesterol, assisting the absorption of iron, and necessary for the maintenance of healthy bones, teeth, gums, skin and blood vessels. Natural Factors Vitamin C Crystals is pure Vitamin C that can be mixed in foods or liquids to meet daily requirements.