cosmetic - Vitamin C powder is used in skin care lotions, creams, serums and other products formulated to stimulate collagen production and lighten or even skin tone. It is also a potent antioxidant ingredient and preservative.culinary - Add vitamin C powder directly to hot or iced teas, shakes, smoothies and other beverages. It may also be mixed with plain water.wellness - The powder may be encapsulated as a dietary supplement.industrial - Vitamin C powder is used in the cosmetic, food and beverage and pharmaceutical industries.safety - Large doses may cause stomach upset, heartburn, or diarrhea. Vitamin C may reduce the effectiveness of anticoagulants, chemotherapy agents, protease inhibitors and statin drugs. It may also increase the absorption of aluminum from certain medications, such as phosphate binders . Consult your physician if you have kidney disease or other chronic condition or if you take pharmaceutical medications.