{
  "id": "vitamin-c",
  "idVersion": 1,
  "ingredient": "Vitamin C (topical)",
  "route": "topical",
  "grade": "moderate",
  "gradeLabel": "Moderate",
  "claim": "Studied in relation to brighter, more even-looking skin and collagen support over time. Formulation and freshness matter.",
  "caveat": null,
  "published": "2026-09-19",
  "sources": [
    {
      "url": "https://pubmed.ncbi.nlm.nih.gov/11896774/",
      "journal": "Dermatologic Surgery",
      "year": 2002,
      "n": null,
      "design": "Double-blind half-face trial",
      "duration": "12 weeks",
      "percentages": [],
      "outcome": "photoaging score",
      "finding": "Double-blind half-face trial: vitamin C side showed significant photoaging-score improvement at 12 weeks (cheeks P=0.006).",
      "formulation": null
    },
    {
      "url": "https://pubmed.ncbi.nlm.nih.gov/16029672/",
      "journal": "Dermatologic Surgery",
      "year": 2005,
      "n": null,
      "design": "Review",
      "duration": null,
      "percentages": [],
      "outcome": "collagen synthesis, photoprotection, pigmentation",
      "finding": "Review: support for topical vitamin C in collagen synthesis, photoprotection (adjunct, not a sunscreen) and pigmentation.",
      "formulation": null
    }
  ],
  "peopleReport": null
}