Is retinol the same thing as dietary vitamin A?

Retinol and vitamin A belong to the same chemical family, but applying something to skin and obtaining a nutrient from food are different matters.

What is retinol?

Retinol is a form of vitamin A. The same molecule is both a dietary nutrient and an ingredient in topical products, so what differs between the two uses is the route, not the substance. As a topical ingredient it sits in the cosmetics category, under a separate set of rules from dietary supplements.

What does dietary vitamin A do?

The annex to Thai Ministry of Public Health Notification No. 447 (B.E. 2566) recognises several statements: vitamin A has a role in body growth; contributes to the maintenance of normal vision, normal mucous membranes and normal skin; contributes to normal iron metabolism; and contributes to the normal function of the immune system.

These describe normal physiology, not an effect produced by topical application.

Can eating vitamin A replace applying retinol?

They are separate routes. What is applied to skin and what the body takes in from food work through different systems. Getting enough vitamin A is a matter of basic nutrition.

Which other nutrients relate to skin?

Under the same annex, zinc contributes to the maintenance of normal skin, hair and nails; biotin contributes to the maintenance of normal skin and hair; and vitamin C contributes to normal collagen formation for the normal function of skin.

Can you have too much vitamin A?

Vitamin A is fat-soluble and accumulates, so an upper intake level is set. For adults it is 3,000 micrograms RAE a day from preformed retinol.

Beta-carotene, found in yellow and orange vegetables and fruit, is a precursor of vitamin A.

How do the two divide up?

Topical products work at the surface of the skin. Nutrition supports the normal working of the body as a whole. Neither substitutes for the other.

Dietary supplements are not intended to prevent, treat or cure any disease.