{"product_id":"cos-de-baha-va-serum-vitamine-c-15-pd-0475","title":"Cos De Baha — VA Vitamin C 15% Pure Ascorbic Acid Serum 30ml","description":"\u003cp\u003eAscorbic acid (vitamin C, L-AA form) is the most active and studied form of vitamin C in cosmetology. It acts simultaneously as a powerful antioxidant, tyrosinase inhibitor, and co-factor in collagen synthesis. Its drawback is oxidative instability: it degrades upon contact with light, air, and metals, requiring careful formulation at an acidic pH (generally 2.5-3.5) and rigorous storage conditions.\u003c\/p\u003e\n\u003cp\u003eCos De Baha's VA Serum is for skin seeking the most direct effect of vitamin C. At 15%, the concentration is within the documented efficacy range—antioxidation, radiance, and melanogenesis inhibition—without reaching the irritating levels of 20-30% formulas. Propanediol as the first ingredient stabilizes the medium and facilitates the dissolution of ascorbic acid. Arbutin (beta-arbutin, position 4) provides a secondary depigmenting action on light spots. Arginine partially buffers the pH. Panthenol supports the skin barrier.\u003c\/p\u003e\n\u003cp\u003eNote regarding short shelf life (07\/2027): this serum must be used quickly after opening. Store away from light and heat—temperature fluctuations accelerate the oxidation of ascorbic acid. If the serum turns dark yellow to brownish-orange, it is partially oxidized, and its effectiveness is reduced.\u003c\/p\u003e\n\u003cp\u003eApply 1 to 2 drops in the morning after cleansing and toning, before cream and sunscreen. Pure ascorbic acid is photosensitizing—it should not be used in the evening (possible interaction with retinol) or without SPF 50+ in the morning. At pH ~3, apply it first to dry skin, before any other serum with a more neutral pH.\u003c\/p\u003e\n\u003cp\u003eIn the morning routine: VA serum first, then SPF 50+ sunscreen. The combination of L-AA + niacinamide is regularly debated: as a precaution, alternate morning (vitamin C) and evening (niacinamide) rather than layering them in the same application.\u003c\/p\u003e","brand":"Cos De Baha","offers":[{"title":"Default Title","offer_id":53898327032145,"sku":"PD-0475","price":15.39,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1032\/7094\/1009\/files\/cos-de-baha-va-serum-vitamine-c-15-pd-0475-1-hd.jpg?v=1788396196","url":"https:\/\/paradermia.com\/en\/products\/cos-de-baha-va-serum-vitamine-c-15-pd-0475","provider":"Paradermia","version":"1.0","type":"link"}