Vitamin A
Vitamin A is an essential vitamin — a fat-soluble vitamin found as preformed vitamin A (retinoids) or as provitamin A carotenoids. 110 peer-reviewed studies are available in our database. Common forms include Retinol, Retinyl Palmitate, Beta-Carotene.
Content reviewed by ZYNAVA Research Team · Last updated February 2026 · Editorial policy
Find Quality Vitamin A Supplements
Explore vitamin a supplements and browse options based on ingredient research.
What Is Vitamin A?
A fat-soluble vitamin found as preformed vitamin A (retinoids) or as provitamin A carotenoids.
Key fact: Beta-carotene is converted to vitamin A as needed.
Vitamin A Supplement Forms
Vitamin A is available in several supplemental forms: Retinol, Retinyl Palmitate, Beta-Carotene, Mixed Carotenoids. Beta-carotene is converted to vitamin A as needed.
Explore Vitamin A Supplements
Use our research tool to explore vitamin a supplements and see what studies have examined.
Research Studies on Vitamin A
Our database contains 110 peer-reviewed studies examining vitamin a. Below are selected recent studies:
Related Supplements
Natural Food Sources of Vitamin A
Before considering supplementation, it is worth exploring dietary sources of vitamin a. Whole foods provide nutrients in their natural matrix alongside fiber, enzymes, and other beneficial compounds that can enhance absorption and utilization.
- Sweet potatoes — One medium baked sweet potato provides over 150% of the daily value as beta-carotene
- Beef liver — One of the most concentrated sources, with a 3 oz serving providing over 400% of the daily value
- Carrots — A half cup of raw carrots provides about 50% of the daily value
- Spinach — Rich in beta-carotene, a half cup of cooked spinach provides about 60% of the daily value
- Cantaloupe — A cup provides about 30% of the daily value
- Red bell peppers — A good source of provitamin A carotenoids
Dietary Context
Vitamin A occurs naturally in two forms: preformed vitamin A (retinol) found in animal products, and provitamin A carotenoids (primarily beta-carotene) found in colorful fruits and vegetables. The body converts beta-carotene into active vitamin A as needed, which provides a natural safeguard against excessive intake from plant sources.
Absorption: Food vs. Supplements
Fat-soluble vitamin A is better absorbed when consumed with dietary fat. Cooking vegetables like carrots and sweet potatoes can actually increase the bioavailability of beta-carotene by breaking down cell walls.
Practical Tips
- Pair orange and dark green vegetables with a source of healthy fat for better absorption
- Both raw and cooked vegetables provide vitamin A, though cooking can enhance carotenoid availability
- A diverse diet with colorful produce typically meets daily vitamin A needs
How to Take Vitamin A
To optimize the benefits of vitamin a supplementation, consider these practical guidelines on timing, food pairing, and potential interactions based on available research.
Best time to take: With a meal containing fat
With or Without Food
Vitamin A is fat-soluble and requires dietary fat for absorption. Taking with a meal that includes healthy fats like olive oil, avocado, or nuts significantly improves uptake.
How Often
Once daily with a fat-containing meal. Do not exceed the tolerable upper limit of 3,000 mcg (10,000 IU) per day from preformed vitamin A.
Practical Tips
- Take with your largest meal of the day, which typically contains the most fat
- Beta-carotene supplements have a much lower toxicity risk than preformed retinol
- Store away from heat and light to preserve potency
Important Interactions
- Do not combine with retinoid medications (isotretinoin, tretinoin) — risk of toxicity
- Orlistat and other fat-blocking medications may reduce absorption
- Excessive alcohol use combined with high vitamin A intake increases liver damage risk
This is not an exhaustive list of interactions. Always consult a healthcare provider or pharmacist about potential interactions with your specific medications and health conditions.
Where to Find Vitamin A Supplements
Ready to explore vitamin a supplements? These reputable retailers offer a range of options with customer reviews and competitive pricing. Always compare products by checking the amount of active ingredient per serving.
How to Choose a Quality Vitamin A Supplement
- Verify the expiration date and that the product is stored appropriately
- Research the brand — established companies with transparent testing are generally more reliable
- Consider subscription options for supplements you plan to take long-term — many retailers offer discounts
- Check the other ingredients list for potential allergens (soy, gluten, dairy, nuts)
To explore supplements by ingredient or health goal, try our AI Supplement Advisor.
Research Highlights: Vitamin A
Published research on vitamin a spans 2025 to 2026 and includes 3 meta-analysiss, 2 reviews, 1 systematic review. The selected summaries below provide an overview of what these studies examined and found. Evidence quality varies across studies, and findings should be discussed with a healthcare provider.
Multivitamin and mineral use: A rapid review of meta-analyses on health outcomes
Published in Ageing Res Rev. Study from 2026.
Source: View full study on PubMed
Vitamin A supplementation coverage and its associated factors among children 6-59 months of age in Ethiopia: a systematic review and meta-analysis
Published in Front Public Health. Study from 2025. Comprehensive analysis combining multiple studies.
Source: View full study on PubMed
Interventions to improve vitamin and mineral inadequacies among children in India: a scoping review
Published in J Hum Nutr Diet. Study from 2025.
Source: View full study on PubMed
Vitamin A supplementation coverage and associated factors among Ethiopian children under five years: a systematic review and meta-analysis
Published in BMC Pediatr. Study from 2025. Comprehensive analysis combining multiple studies.
Source: View full study on PubMed
Barriers and facilitators to the implementation of vitamin A supplementation programs in Africa: A systematic review
Published in Nutr Health. Study from 2025. Comprehensive analysis combining multiple studies.
Source: View full study on PubMed
Effect of carotenoid supplementation on blood pressure in adults: a GRADE-assessed systematic review and dose-response meta-analysis of randomized controlled trials
Published in Nutr Rev. Study from 2025. Comprehensive analysis combining multiple studies.
Source: View full study on PubMed
The research summaries above are based on published peer-reviewed studies and are provided for informational purposes only. Study findings may not apply to all individuals, and the presence of a study summary does not constitute an endorsement of vitamin a for any specific health condition. Always consult a qualified healthcare professional before making decisions based on research findings.
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