Retinol is a form of vitamin A,  a lipophilic molecule which can be obtained from animal sources like liver, fish, and dairy products. It can also be synthesized in the lab.

The name describes the structure of the molecule:

• "Retinol" is derived from "retina", as retinol is a form of vitamin A that plays a crucial role in the retina's function in the eye. Also known as Vitamin A1, retinol is part of a family of compounds called retinoids. These compounds are structural and functional analogs of retinol.

Description of raw materials used in production.

• While retinol can be sourced from natural means, for industrial purposes, it's often produced synthetically. Beta-carotene, a carotenoid found in many plants like carrots and spinach, is one of the major raw materials.

Step-by-step summary of industrial chemical synthesis process.

• Extraction of beta-carotene from plant sources using solvents.
• Oxidation of beta-carotene to form retinaldehyde.
• Reduction of retinaldehyde to produce retinol.

Pure retinol is a pale-yellow to yellow-orange crystalline solid.

What it is for and where

Medical

Retinol can accelerate the healing process from wounds (1).

Acne Therapies. Topical forms of retinol, like tretinoin, have been used for decades in treating acne. They work by regulating the growth and differentiation of skin cells.

Psoriasis Therapies. Tretinoin can also be used to treat psoriasis, a condition where skin cells grow too quickly, leading to scaly lesions.

Skin Cancers. Retinol derivatives have been explored as potential treatments for certain skin cancers.

Safety

Retinol can be toxic if taken in excess, and the elderly may be particularly at risk for hypervitaminosis (2).

Cosmetics

Retinol is used in cosmetics as an anti-aging and firming agent (3).

As an INCI ingredient it has the following functions:

Skin conditioning agent. It is the mainstay of topical skin treatment as it has the function of restoring, increasing or improving skin tolerance to external factors, including melanocyte tolerance. The most important function of the conditioning agent is to prevent skin dehydration, but the subject is rather complex and involves emollients and humectants that can be added in the formulation.

Skin conditioning agent - Miscellaneous.  This ingredient has the task of modifying and improving the condition of the skin when it is damaged or dry, reducing flaking and restoring its elasticity.

Commercial Applications

Cosmetics. Beyond its effects on aging and acne, retinol can also assist in lightening dark spots, reducing hyperpigmentation, and minimizing the appearance of pores.

Photoprotection. While retinol may make the skin more sensitive to sunlight, some research suggests it can offer some protection against sun damage when used in conjunction with sun protection products.

• Molecular Formula  C₂₀H₃₀O
• Molecular Weight   286.5 g/mol
• CAS   68-26-8   11103-57-4
• UNII    G2SH0XKK91
• EC Number   200-683-7   234-328-2
• DTXSID3023556

Chemical Safety

Synonyms:

• Vitamin A1

References_____________________________________________________________________

(1) Polcz ME, Barbul A. The Role of Vitamin A in Wound Healing. Nutr Clin Pract. 2019 Oct;34(5):695-700. doi: 10.1002/ncp.10376. 

(2) Ward BJ. Retinol (vitamin A) supplements in the elderly. Drugs Aging. 1996 Jul;9(1):48-59. doi: 10.2165/00002512-199609010-00005. 

Abstract. Aging is associated with many changes in epithelial tissues, immune function and haematopoiesis-myelopoiesis. There is increasing evidence that retinoids can significantly influence some of these changes. Retinoids may also have anticancer effects and protect against age-associated conditions such as macular degeneration. However, retinol (vitamin A) can be toxic when taken in excess and the elderly may be at particular risk for hypervitaminosis A. Evaluation of elderly people ingesting significantly more or less than the recommended daily intake of retinol requires an understanding of the biology of retinoids and consideration of the relative risks and benefits of supplementation.

(3) Salas T, Bordes C, Arquier D, Caillier L, Mandica F, Bolzinger MA. Effect of massage on retinol skin penetration. Int J Pharm. 2023 Jul 25;642:123106. doi: 10.1016/j.ijpharm.2023.123106.