Active Ingredient Glossary

Ferulic Acid: The Vitamin C Booster

Active Ingredients Glossary · F INCI: Ferulic Acid Ferulic acid is rarely the star on the label—yet it's one of the most important ingredients on high-quality INCI lists. This plant-based antioxidant stabilizes sensitive active ingredients like vitamin C and enhances their protective effects. Anyone buying a vitamin C serum should look for this booster. Profile Research Combats free radicals, oxidative stress, and a dull complexion Skin Type: All Concentration 0.5–1% RoutineIn the morning, with vitamin C and sunscreen Tolerance: None required What is ferulic acid? Ferulic acid is a hydroxycinnamic acid—a plant-based antioxidant found in the cell walls of rice, oats, bran, and many seeds. There, it protects the plant from oxidative stress; in skincare, it plays exactly the same role for your skin and for the formulation itself. Ferulic acid gained fame through the classic antioxidant combination of vitamin C, vitamin E, and ferulic acid, which is still considered the gold standard of modern vitamin C serums today. The reason: Pure ascorbic acid is unstable—it oxidizes quickly and loses its effectiveness in the process. Ferulic acid stabilizes the formula, extends its shelf life, and, as an antioxidant, provides its own protective benefits. Effect: What's Been Proven Four out of five bars—with one important caveat: Ferulic acid has been most extensively studied in combination with other ingredients. Studies show that the trio of vitamin C, vitamin E, and ferulic acid can significantly enhance antioxidant protection compared to the individual ingredients—the skin is better shielded from free radicals generated by UV light and environmental factors. Its stabilizing effect on vitamin C is also well documented. As a standalone ingredient, the evidence is more limited—ferulic acid truly shines as a team player, not as the star of the show. Application & Combination You'll almost always find ferulic acid as an ingredient in a ready-made serum—usually a vitamin C serum for the morning. Apply it after cleansing, followed by moisturizer and sunscreen. No adjustment period is needed; the active ingredient is considered well-tolerated. Good Combinations ✓ Vitamin C – ferulic acid stabilizes and enhances it ✓ Vitamin E – completes the classic antioxidant trio ✓ Sunscreen – antioxidants ideally complement the UV filter Note ! Works best in carefully designed combination formulations—rarely effective as a standalone product ! Antioxidants complement sun protection but never replace it Ferulic acid in the BONSANA lineup MAD HIPPIEVitamin C Serum with Ferulic AcidCHF 29.9030 ml Shop Now Discover antioxidant serums Vitamin C with ferulic acid and other facial serums—verified brands, ready to ship from our Swiss warehouse. View facial serums → Related entries: Vitamin C · Niacinamide · CoQ10 · Read more: Skin after summer vacation: Restoring moisture Frequently Asked Questions About Ferulic Acid What does ferulic acid do in a vitamin C serum? It serves two purposes: As a stabilizer, it slows the oxidation of sensitive ascorbic acid, and as an antioxidant in its own right, it enhances protection against free radicals. That's why this combination is considered the gold standard. Can I use ferulic acid on its own? Theoretically, yes, but in practice, it rarely makes sense. Ferulic acid's strengths lie in its combination with vitamin C and vitamin E—as a standalone ingredient, the evidence is limited and product options are scarce. When should I apply ferulic acid? In the morning, as part of your antioxidant serum after cleansing. Follow with moisturizer and sunscreen—this way, UV filters and radical protection complement each other perfectly. Is ferulic acid an acid like AHA or BHA? No. Despite its name, ferulic acid does not exfoliate—it's an antioxidant, not an exfoliating acid. Therefore, there's no need for a build-up period like with fruit acids.