Safety Profile
Known Safety Concerns
- Teratogenic at high doses -- contraindicated in pregnancy
- Fat-soluble -- accumulates in liver with excess intake
- UL 3,000 mcg RAE per day -- easily exceeded when stacking supplements
- Increased fracture risk at chronic high intakes above 1,500 mcg per day
Contraindications
- Teratogenic at high doses -- contraindicated in pregnancy
- Fat-soluble -- accumulates in liver with excess intake
Interactions
Information not yet available for this ingredient profile.
Evidence and Scientific Findings
Ingredient Overview
Retinyl palmitate is the most common ester form of preformed vitamin A used in supplements and fortified foods. Like retinol, it is fat-soluble and accumulates in the liver with excess intake. Teratogenic at high doses in pregnancy. The UL is 3,000 mcg RAE per day for adults. Widely used in multivitamins and skin supplements.
Biological and Chemical Classification
- Scientific Name
- Retinyl palmitate
Mechanism of Action
Information not yet available for this ingredient profile.
Clinical Evidence of Effectiveness
Information not yet available for this ingredient profile.
Pharmacokinetics
Information not yet available for this ingredient profile.
Recommended Dosage
Information not yet available for this ingredient profile.
SETI — Scientific Evidence Transparency Index
Executive Summary — Ingredient Assessment
- 10 studies reviewed
- 0 high-quality studies (meta-analysis or RCT)
- Main clinical benefit observed: Vitamin
- Evidence consistency: High consistency across studies (100%)
- Teratogenic at high doses -- contraindicated in pregnancy
- Fat-soluble -- accumulates in liver with excess intake
- UL 3,000 mcg RAE per day -- easily exceeded when stacking supplements
- Increased fracture risk at chronic high intakes above 1,500 mcg per day
The available scientific evidence for Vitamin A (Retinyl Palmitate) indicates notable safety signals that warrant caution. Use should be considered carefully and monitored, particularly in sensitive populations or alongside other medications.
Total SETI Score
High risk| Evidence quality | 10/40 |
| Evidence consistency | 20/20 |
| Safety signals | 0/20 |
| Study recency | 10/10 |
| Evidence transparency | 10/10 |
Evidence Summary
- 10 studies reviewed
- 0 high-quality studies (meta-analysis or systematic review)
- 0 studies identified benefits or no safety concern (GREEN)
- 10 studies reported limited or advisory safety evidence (YELLOW)
Evidence Policy
Only peer-reviewed scientific literature indexed in PubMed or comparable databases is included in this evaluation. Commercial websites, blogs, and marketing materials are excluded. All references include direct traceable links to source documents.
Last updated: 24 მარ 2026, 07:53
Evidence Distribution
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Observational / other LOW evidence YELLOWState-of-the-art on absorption mechanisms and factors affecting the bioavailability of preformed vitamin A. ↗Borel P et al.. State-of-the-art on absorption mechanisms and factors affecting the bioavailability of preformed vitamin A.. Prog Lipid Res. 2026. PMID:41850408.PMID 41850408 ↗Journal Prog Lipid ResYear 2026Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/41850408/
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Observational / other LOW evidence YELLOWNon-Fat Fermented Milk Enhanced the Bioavailability of Fat-Soluble Vitamins in Humans: A Crossover Study. ↗Morifuji M et al.. Non-Fat Fermented Milk Enhanced the Bioavailability of Fat-Soluble Vitamins in Humans: A Crossover Study.. J Nutr Sci Vitaminol (Tokyo). 2026. PMID:41765411.PMID 41765411 ↗Journal J Nutr Sci Vitaminol (Tokyo)Year 2026Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/41765411/
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Observational / other LOW evidence YELLOWIn Vivo Two-Dimensional Correlation Raman Spectroscopy Unveiling the Reversible Microstructural Changes and Spatially Differential Swelling of the Human Stratum Corneum in Response… ↗Yang Y et al.. In Vivo Two-Dimensional Correlation Raman Spectroscopy Unveiling the Reversible Microstructural Changes and Spatially Differential Swelling of the Human Stratum Corneum in Response to Glycerin as a Temporary Penetration Enhancer.. Anal Chem. 2026. PMID:41670962.PMID 41670962 ↗Journal Anal ChemYear 2026Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/41670962/
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Observational / other LOW evidence YELLOWTracking Systemic and Ocular Vitamin A. ↗Montenegro D et al.. Tracking Systemic and Ocular Vitamin A.. Cells. 2026. PMID:41597238.PMID 41597238 ↗Journal CellsYear 2026Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/41597238/
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Observational / other LOW evidence YELLOWMicroneedling accelerates burn wound healing and promotes collagen remodeling: Insights from a rodent model. ↗Alpat SE et al.. Microneedling accelerates burn wound healing and promotes collagen remodeling: Insights from a rodent model.. Burns. 2026. PMID:41380206.PMID 41380206 ↗Journal BurnsYear 2026Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/41380206/
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Observational / other LOW evidence YELLOWVitamin A supplementation during the suckling period attenuates the effects of a maternal Western diet on liver sexual maturity-related traits in a… ↗Abrego-Guandique DM et al.. Vitamin A supplementation during the suckling period attenuates the effects of a maternal Western diet on liver sexual maturity-related traits in a sex-dependent manner.. J Nutr Biochem. 2026. PMID:41109574.PMID 41109574 ↗Journal J Nutr BiochemYear 2026Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/41109574/
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Observational / other LOW evidence YELLOWTake a deep breath: the important role of vitamin A in neonatal lung development and visiting the potential of aerosolized delivery for… ↗Rehan VK et al.. Take a deep breath: the important role of vitamin A in neonatal lung development and visiting the potential of aerosolized delivery for bronchopulmonary dysplasia prevention.. Expert Rev Respir Med. 2026. PMID:40874692.PMID 40874692 ↗Journal Expert Rev Respir MedYear 2026Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/40874692/
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Observational / other LOW evidence YELLOWPerinatal vitamin A excess impacts vitamin A and lipid metabolism in rat offspring. ↗Berthomu00e9 A et al.. Perinatal vitamin A excess impacts vitamin A and lipid metabolism in rat offspring.. Sci Rep. 2025. PMID:41057405.PMID 41057405 ↗Journal Sci RepYear 2025Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/41057405/
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Observational / other LOW evidence YELLOWIntranasal zinc and vitamin A treatments alter response to bovine respiratory syncytial virus and Mannheimia haemolytica co-infection. ↗Rients EL et al.. Intranasal zinc and vitamin A treatments alter response to bovine respiratory syncytial virus and Mannheimia haemolytica co-infection.. Transl Anim Sci. 2025. PMID:40927235.PMID 40927235 ↗Journal Transl Anim SciYear 2025Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/40927235/
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Observational / other LOW evidence YELLOWDo serum vitamins, carotenoids, and retinyl esters influence mortality in osteoarthritis? Insights from a nationally representative study. ↗Lu Y et al.. Do serum vitamins, carotenoids, and retinyl esters influence mortality in osteoarthritis? Insights from a nationally representative study.. Front Nutr. 2025. PMID:40612304.PMID 40612304 ↗Journal Front NutrYear 2025Study type Observational / otherEvidence strength LOW evidencePubMed link https://pubmed.ncbi.nlm.nih.gov/40612304/
Score Transparency
0 of 10 approved references (score saturates at 10). More peer-reviewed studies = stronger evidence base.
Method: Q = number of approved references ÷ 10 (capped at 1.0)
Limited — mostly case reports or animal studies
Method: L = mean study-level weight across approved references. Level 1 (meta-analysis / systematic review) = 1.0; Level 2 (RCT) = 0.8; Level 3 (cohort/case-control) = 0.6; Level 4 (case report) = 0.4; Level 5 (animal / in-vitro) = 0.2.
Mixed or neutral — roughly equal benefit and risk signals
Method: D = (sum of risk-scored references − sum of benefit-scored references) ÷ total evidence score, then scaled from [−1, 1] to [0, 1]. 0.0 = pure benefit; 0.5 = neutral; 1.0 = pure risk.
One or more monitoring-level safety signals active
Method: S = 0.5 (neutral baseline) + sum of active signal severity deltas ÷ 10. Severity deltas: Critical = +2.0, High = +1.5, Moderate = +1.0, Low = +0.5. Capped at 1.0.
Final GIRI Score for Vitamin A (Retinyl Palmitate). Risk level thresholds: Low 0–3.0 · Moderate 3.0–5.5 · High 5.5–7.5 · Critical 7.5–10.
Full methodology & data sources
The GIRI Score is computed entirely from structured data — no editorial scoring or subjective weighting is applied at any step.
- References: Only approved references are counted. Each reference is assigned an evidence level (L1–L5) and a direction (risk / neutral / benefit) by the reference manager or AI classifier.
- Safety Signals: Sourced from regulatory agencies (FDA, EMA, Health Canada, TGA, and others) and pharmacovigilance databases. Only active signals count toward the score.
- Formula version: GIRI Score v3.7.0 — Q × L × D × S × 10.
- Limitations: The score reflects published evidence and recorded signals as of the last update date. It is not a clinical risk assessment and should not replace advice from a qualified healthcare professional.
Risk Level Classification
Based on available regulatory signals and scientific evidence, this ingredient presents a moderate safety concern. Caution is advised, particularly at high doses or in sensitive populations.
0–3.0
3.0–5.5
5.5–7.5
7.5–10
The score pin shows exactly where this ingredient falls on the fixed risk scale.
What drove the Moderate classification for Vitamin A (Retinyl Palmitate)
A score of 5.0 places this ingredient in the Moderate band. Thresholds: Low 0–3.0 · Moderate 3.0–5.5 · High 5.5–7.5 · Critical 7.5–10.
0 approved references.
Limited — mostly case reports or animal studies (Level 4–5).
Neutral or mixed — benefit and risk signals roughly balanced.
No active signals — S component is at neutral baseline (0.5), contributing no extra risk weight.
No major regulatory restrictions or advisories recorded across monitored jurisdictions (FDA, EMA, Health Canada, TGA, and others).
How are the Low / Moderate / High / Critical thresholds defined?
The four risk levels are fixed score bands. A score is assigned to exactly one level based on where it falls:
| Level | Score | Meaning |
|---|---|---|
| LOW | 0.0 – 2.9 | Sparse or predominantly beneficial evidence. No active safety alerts. |
| MODERATE | 3.0 – 5.4 | Mixed signals — some risk alongside benefit. Caution at high doses or in sensitive groups. |
| HIGH | 5.5 – 7.4 | Multiple studies or regulatory alerts documenting adverse effects. Professional oversight recommended. |
| CRITICAL | 7.5 – 10 | Regulatory restrictions in one or more major jurisdictions. Serious documented harm. Avoid without specialist supervision. |
Thresholds are fixed constants (GIRI_Score_Utils::LEVEL_THRESHOLDS). They do not change per ingredient and are never subject to editorial adjustment.