Retinol

A systematic review of nine randomized, double-blind, vehicle-controlled trials of over-the-counter retinol products for facial aging found that four studies showed no significant benefit over vehicle and the remaining five had major methodological flaws, supporting only weak evidence for retinol providing mild improvements in fine wrinkles.

In an 8-week observational study of healthy adults using facial serums with 0.15% or 0.3% retinol, both concentrations improved overall skin condition, color, hydration, radiance, and subjective wrinkle assessments, with only minimal reports of burning, dryness, pruritus, and erythema.

Topical application of retinol to photoaged facial skin in healthy volunteers produced significant changes in epidermal and dermal histology and molecular markers, along with clinical improvements in some aging signs, indicating that retinol can induce retinoid-like remodeling of human skin.

A systematic review of nine randomized, double-blind, vehicle-controlled trials of over-the-counter retinol products for facial aging found that four studies showed no significant benefit over vehicle and the remaining five had major methodological flaws, supporting only weak evidence for retinol providing mild improvements in fine wrinkles.

In an 8-week observational study of healthy adults using facial serums with 0.15% or 0.3% retinol, both concentrations improved overall skin condition, color, hydration, radiance, and subjective wrinkle assessments, with only minimal reports of burning, dryness, pruritus, and erythema.

Topical application of retinol to photoaged facial skin in healthy volunteers produced significant changes in epidermal and dermal histology and molecular markers, along with clinical improvements in some aging signs, indicating that retinol can induce retinoid-like remodeling of human skin.

In adults with age-related macular degeneration, oral supplementation with 16,000 IU vitamin A daily for eight weeks partially improved measures of dark adaptation and cone sensitivity compared with baseline, suggesting functional visual benefits but at doses above typical dietary recommendations.

In a large trial of periodic oral retinol in children, supplementation every six months substantially reduced the prevalence of severe vitamin A deficiency markers without evidence of major toxicity, demonstrating effectiveness of retinol in improving vitamin A status in otherwise generally healthy populations at risk of deficiency.

Among adults receiving long-term high-dose retinol supplementation, markedly elevated plasma retinol concentrations were not associated with increased risk of any fracture or osteoporotic fracture, countering earlier observational concerns about retinol and bone fragility, although the study was not designed to show benefit.

In adults with age-related macular degeneration, oral supplementation with 16,000 IU vitamin A daily for eight weeks partially improved measures of dark adaptation and cone sensitivity compared with baseline, suggesting functional visual benefits but at doses above typical dietary recommendations.

In an 8-week observational study of healthy adults using facial serums with 0.15% or 0.3% retinol, both concentrations improved overall skin condition, color, hydration, radiance, and subjective wrinkle assessments, with only minimal reports of burning, dryness, pruritus, and erythema.