Vitamin A

Retinol, retinal, retinoic acid; provitamin A carotenoids

Fat-soluble vitamins

Aliases / common names

Retinol; beta-carotene; retinyl palmitate; retinyl acetate

Natural food sources

Liver, fish liver oil, egg yolk, dairy; orange and dark-green vegetables provide provitamin A carotenoids.

Main wellness functions

Supports normal vision, epithelial integrity, immune function, growth and reproduction.

Deficiency signs

Night blindness, dry eyes, xerophthalmia, impaired immunity and poor growth in children.

Recommended intake

Adults: 700 mcg RAE/day women, 900 mcg RAE/day men. Children: about 300-600 mcg RAE/day by age. Pregnancy: 770 mcg RAE/day. Adult UL: 3,000 mcg RAE/day preformed vitamin A.

Excess intake effects

Preformed vitamin A excess can cause headache, liver toxicity, bone pain, skin changes and birth-defect risk. Beta-carotene can discolor skin but is not equivalent to retinol toxicity.

Contraindicated / caution groups

Pregnant people, liver disease patients, heavy alcohol users and people taking retinoid medicines should avoid high-dose retinol unless supervised.

Common dosage forms

Softgels, tablets, drops, multivitamins; retinyl palmitate/acetate or beta-carotene.

Common product strengths

750-3,000 mcg RAE or 2,500-10,000 IU; beta-carotene often 3-15 mg.

Use precautions

Check whether IU refers to retinol or beta-carotene. Avoid stacking multiple retinol-containing products.

Supplement notes

Fat improves absorption. Smokers should avoid high-dose beta-carotene supplements due to lung cancer signal in trials.

This information is for general nutrition education and product reference only. It does not replace medical diagnosis, treatment or individualized dietary advice.