{"title":"Retinaldehyde","entity_type":"Ingredient","slug":"retinaldehyde","canonical_url":"https://skinknowledgebase.com/ingredients/retinaldehyde","dates":{"date_modified":"2026-05-18","date_reviewed":"2026-05-18"},"mcp_eligible":true,"evidence_sources":[{"title":"AAD — Retinoid or retinol?","canonical_citation_url":"https://skinknowledgebase.com/sources/aad-retinoid-or-retinol","original_source_url":"https://www.aad.org/public/everyday-care/skin-care-secrets/anti-aging/retinoid-retinol","source_type":"dermatology_reference"},{"title":"DermNet NZ — Topical retinoids","canonical_citation_url":"https://skinknowledgebase.com/sources/dermnet-topical-retinoids","original_source_url":"https://dermnetnz.org/topics/topical-retinoids","source_type":"medical_reference"}],"product_fact_sources":[{"title":"Official Product Page — Medik8 Crystal Retinal","canonical_citation_url":"https://skinknowledgebase.com/sources/official-product-page-medik8-crystal-retinal","original_source_url":"https://us.medik8.com/products/crystal-retinal","source_type":"official_product_page"}],"related_entities":[{"title":"AAD — Retinoid or retinol?","url":"https://skinknowledgebase.com/sources/aad-retinoid-or-retinol"},{"title":"DermNet NZ — Topical retinoids","url":"https://skinknowledgebase.com/sources/dermnet-topical-retinoids"},{"title":"Official Product Page — Medik8 Crystal Retinal","url":"https://skinknowledgebase.com/sources/official-product-page-medik8-crystal-retinal"},{"title":"Wrinkles","url":"https://skinknowledgebase.com/concerns/wrinkles"},{"title":"Fine Lines","url":"https://skinknowledgebase.com/concerns/fine-lines"},{"title":"Loss of Firmness","url":"https://skinknowledgebase.com/concerns/loss-of-firmness"},{"title":"Expression Lines","url":"https://skinknowledgebase.com/concerns/expression-lines"},{"title":"Medik8 Crystal Retinal","url":"https://skinknowledgebase.com/products/medik8-crystal-retinal"},{"title":"Retinoid Dermatitis","url":"https://skinknowledgebase.com/side-effects/retinoid-dermatitis"}],"body_sections":[{"heading":"Quick Summary","paragraphs":["Retinaldehyde, also called retinal, is a vitamin A ingredient used in cosmetic skincare routines for visible texture, tone, and fine-line appearance."]},{"heading":"What It Is","paragraphs":["Retinaldehyde is a vitamin A ingredient that sits in the broader retinoid family. Consumers often see it labeled as retinal or retinaldehyde on skincare pages. It is distinct from retinol and prescription retinoids, so it deserves its own ingredient page when a product’s search interest centers on retinal strength, routine tolerance, and nighttime vitamin A use. In Medik8 Crystal Retinal, the brand page presents retinal as the central active in a progressive strength ladder."]}],"side_effects":[{"title":"Retinoid Dermatitis","url":"https://skinknowledgebase.com/side-effects/retinoid-dermatitis"}]}