Vitamin A is a fat-soluble vitamin that naturally occurs in foods like carrots, sweet potatoes, and liver. It plays a critical role in maintaining healthy vision, supporting immune function, and aiding in the growth and development of cells. Research extensively highlights its importance in eye health, particularly in preventing night blindness and age-related macular degeneration. Studies also suggest that adequate vitamin A intake supports skin health and the proper functioning of the immune s

How many studies on Vitamin A are available?

NutriVouch references 533 human studies on Vitamin A, all peer-reviewed and indexed on PubMed.

Is Vitamin A effective for Eye Health?

For Eye Health, Vitamin A has an effectiveness score of 9/10 — gold-standard treatment with strong clinical evidence. Based on 13 relevant studies.

Is Vitamin A effective for Immune Support?

For Immune Support, Vitamin A has an effectiveness score of 7/10 — strong evidence supporting clinical use. Based on 22 relevant studies.

Is Vitamin A effective for Skin Health?

For Skin Health, Vitamin A has an effectiveness score of 7/10 — strong evidence supporting clinical use. Based on 19 relevant studies.

Is Vitamin A effective for Prenatal Health?

For Prenatal Health, Vitamin A has an effectiveness score of 6/10 — moderate evidence — works in some populations. Based on 17 relevant studies.

Is Vitamin A effective for Antioxidant Protection?

For Antioxidant Protection, Vitamin A has an effectiveness score of 5/10 — moderate evidence — works in some populations. Based on 10 relevant studies.

Confidence level

Strong evidence

533 studies

Vitamin A

Absorption

✦Take with a fat-containing meal for best absorption, as it is a fat-soluble vitamin. Avoid taking with high doses of vitamin E supplements, which may interfere with absorption.

Daily Dose

⚖

Common dose: 2,500–5,000 IU (750–1,500 mcg RAE) daily

RDA: 900 mcg RAE for men, 700 mcg RAE for women

Upper limit: 3,000 mcg RAE

Best form: Preformed vitamin A (retinol, retinyl palmitate)

Timing: With a fat-containing meal

Excessive intake can lead to toxicity, particularly from supplements and animal sources. Beta-carotene is a safer source for high intake, though conversion efficiency varies.

Effects

🍇 Antioxidant Protection

5.010 studies›

Food Sources

Beef liver6500mcg per 100g
Sweet potato961mcg per 100g
Carrots835mcg per 100g
Spinach469mcg per 100g
Kale681mcg per 100g