Oral Photoprotection: Emerging Role of Nutraceuticals and Functional Dosage Forms a Comprehensive Evidence-Based Review

Background: Photoprotection has traditionally been achieved through topical sunscreens; however, growing evidence supports the systemic modulation of UV-induced skin damage through nutritional and nutraceutical interventions. Oral photoprotection represents a complementary, inside-out approach that targets multiple pathways of photodamage simultaneously. Objectives: This review comprehensively examines the molecular mechanisms, clinical evidence, functional dosage form innovations, and regulatory landscape surrounding oral photoprotective agents including carotenoids, polyphenols, vitamins, botanical extracts, and omega-3 fatty acids. Methods: A systematic narrative review of PubMed, Scopus, Web of Science, and ClinicalTrials.gov databases was conducted, identifying 158 peer-reviewed studies (1995-2024). Inclusion criteria encompassed randomized controlled trials, mechanistic studies, and pharmacokinetic evaluations of oral photoprotective agents. Results: Polypodium leucotomos extract, astaxanthin, lycopene, nicotinamide, and combined antioxidant formulations demonstrate consistent photoprotective efficacy ranging from 15-40% reduction in erythema and 18-45% reduction in UV-induced DNA damage in clinical trials. Advanced delivery systems including nanostructured lipid carriers, self-emulsifying drug delivery systems, and liposomal formulations enhance bioavailability of poorly soluble nutraceuticals by 1.5-4-fold. Conclusions: Oral photoprotection through nutraceuticals constitutes a scientifically validated, safe, and synergistic complement to conventional topical photoprotection. The integration of advanced functional dosage forms addresses critical bioavailability barriers and positions oral photoprotectives as a promising frontier in dermatological and cosmeceutical practice.