Whether you are a skin specialist or someone interested in skin care who regularly visits your dermatologist (skin doctor) for the latest treatment, you are likely familiar with the terms collagen, hyaluronic acid, and retinoids. Vitamin A derivatives (retinoids) are the most widely researched ingredients for reducing wrinkles and fine lines.
However, it's important to understand how retinoids work and which retinoids are best suited for your skin before heading to your local pharmacy or supermarket.
What are retinoids?
Retinoids are a class of compounds derived from vitamin A with a similar structure and function to vitamin A. This class includes retinoic acid, retinaldehyde, retinol, and retinyl esters. Retinoids are widely used in cosmetics due to their anti-ageing properties and various skin benefits.1
Vitamin A and its derivatives (retinoids) reduce fine lines and wrinkles and slow down the ageing process. The fat-soluble retinoids work by penetrating deep into the skin layers and regulating cells. They increase new blood vessel production in the skin, strengthen the skin's protective function, reduce water loss, stimulate collagen production, and reduce collagen breakdown and loss.1,2
How do retinoids work?
Retinoids work by neutralising free radicals (unstable molecules that damage our skin cells), reducing inflammation, improving skin shading, and stimulating the production of new blood vessels. They increase cell turnover to make way for new cells in the skin to replace the older and damaged cells. This results in improving the skin colour and even the skin tone.1
Retinoids also promote the production of hyaluronic acid and collagen, and reduce collagen breakdown that already exists in the skin.3 Collagen is a protein that is responsible for elasticity and youthful-looking skin. As you grow up, your body produces less collagen and starts breaking down the existing ones, leading to sagging skin and the appearance of wrinkles and fine lines.4 However, retinoids’ interaction with collagen reduces its breakdown and helps restore the firmness, smoothness, and elasticity of the skin. This gets rid of some existing fine lines and wrinkles and prevents the formation of new ones.1,3
You are advised to use retinoids regularly for three to six months to notice improvements in your skin. The best results require up to 12 months of regular use.
Different types of retinoids
Retinoids are classified into four groups: retinoic acid, retinaldehyde, retinol, and retinyl esters. All retinoids are available as over-the-counter skin care products except retinoic acid, which is only available in prescription form. Retinoic acid is the strongest and most effective type, however, the other types will be more gentle on your skin and will still make a difference over time.2
This is the most potent form of retinoid and is the biologically active form that vitamin A breaks down into in order to be utilised by the skin. Since retinoic acid is a type of molecule that can be used by the skin instantly without going through any conversions, it is very effective but has the potential to be irritating.
Compared to retinoic acid, other retinoids have larger molecules and need conversions, which makes them weaker than retinoic acid. The more conversions are required, the “weaker” a retinoid is.2
Tretinoin and isotretinoin are the pure forms of retinoic acid. However, they are only available by prescription and must be used consistently and carefully to get the best results.
Tretinoin is a prescription topical form of pure retinoic acid (commonly known as Retin-A). It does not need to undergo any conversion and is considered one of the most popular forms of vitamin A applied topically. It is effective in treating acne, improving skin hyperpigmentation and discolouration, and reducing fine lines and wrinkles.
Since tretinoin is pure retinoic acid, it is associated with some side effects. When you start using tretinoin, expect to see dry patches, irritation, mild flaking, and redness. However, these side effects can be avoided by applying tretinoin two to three times per week, followed by a moisturiser that acclimates the skin. Avoid exposure to sunlight.5
Isotretinoin is a prescription oral form of retinoic acid (commonly known as Accutane) and the most potent of all retinoids, which makes it reserved for severe acne. Isotretinoin treats the persistent form of acne by permanently reducing the size and production of sebaceous glands (oil glands); thus, it has long-term beneficial effects on the skin. Since isotretinoin is a much more intense medication, it is associated with systemic side effects like muscle aches and dry skin, lips, nose, and eyes, in addition to birth defects if taken during pregnancy. Taking a lower dose of isotretinoin over a long time provides a long-term cure for acne with minimal discomfort.6
This is the most popular type of retinoid. It is known for its anti-ageing and skin-renewing properties. Retinol itself is inactive within the skin, it has to be converted to retinoic acid to be active. This is a two-step process that takes place within the cell. Retinol is still very effective, and that's why it is found in many cosmetic formulations.
Retinol has several benefits: it regulates skin cell turnover, prevents acne, reduces hyperpigmentation, controls oil levels, unclogs pores, and prevents fine lines and wrinkles.7
Retinol has a few drawbacks:
- It can cause skin peeling, irritation, and dryness for people with sensitive skin
- Formulations with retinol should be stored in airtight containers as exposure to oxygen could mix with the chemical composition, making it less effective8
- Retinol is photosensitive, which means it should be stored in an opaque container
Top tip: avoid applying retinol during the day, as UV rays can decompose retinol prematurely on your skin, causing photosensitivity and leading to sunburn or rashes.
This is also known as retinal and is considered the most potent non-prescribed retinoid. Retinaldehyde is very close to retinoic acid on the conversion scale, only needing one conversion, making it more potent than retinol and retinyl esters. Therefore, it can cause skin irritation and dryness, however, it is gentler than pure retinoic acid.9
Retinal is similar to retinol as it helps get rid of dead skin cells and replaces them with new ones (cell turnover), improves skin hydration, pigmentation and discolouration, reduces fine lines and wrinkles, and treats acne.10,11
This category of retinoids is the weakest and the least irritating and potent form of retinoid, which makes it perfect for people with sensitive skin. Retinyl esters are made up of larger molecules that require three steps to convert into retinoic acid. At first, it converts to retinol, then retinaldehyde, and finally to retinoic acid. Thus, these derivatives of vitamin A, including retinyl linoleate, retinyl palmitate, retinyl propionate, and retinyl acetate, are quite gentle.12
Do retinoids reduce wrinkles?
Several studies have reported the efficacy of retinoids in improving fine lines and wrinkles. A recent review published in the International Journal of Women's Dermatology concluded that topical retinoids are efficacious in improving the clinical appearance of photoaging (early ageing of the skin caused by repeated exposure to sunlight), such as wrinkles, fine lines, hyperpigmentation, sallowness (unhealthy-looking skin), and lentigines. A total of 180 studies found that topical tretinoin is a safe and effective therapeutic method for the long-term treatment of sun damage.13
Another study showed that a nightly application of hydrating, double-conjugated retinoid eye cream (made up of retinoid and alpha hydroxy acid/AHA) not only reduced fine lines and wrinkles but also improved the overall texture and tone of the skin in the periorbital region (area extending from the upper and lower eyelids to the eyebrows). Participants who used retinoid eye cream experienced a significant improvement in the appearance of fine lines and wrinkles as well as under-eye darkness, puffiness, and dryness of the area around your eyes.14
Do retinoids reduce fine lines?
In addition to their effectiveness in reducing wrinkles, retinoids have also been found to be beneficial in reducing the appearance of fine lines. Fine lines are often the result of repetitive facial expressions and the breakdown of collagen and elastin in the skin. By stimulating collagen production and increasing cell turnover, retinoids can help to plump the skin and smooth out fine lines.
One study found that 3% retinol peel (facial chemical peel) reduced fine lines and wrinkles, as well as acne and hyperpigmentation in participants over a series of 2-4 peels. The study concluded that retinol is an efficacious cosmetic treatment that improves the appearance of fine lines and wrinkles, promoting a bright, even complexion.15
These findings suggest that retinoids can reduce the appearance of fine lines and wrinkles, making them an effective option for individuals looking to combat the signs of ageing.
How to use retinoids
To effectively use retinoids to reduce wrinkles and fine lines, follow these steps:
- Start slowly when introducing retinoids into your routine, start with a low concentration and gradually increase the frequency or strength. This helps to minimise the risk of irritation and allows your skin to acclimate to the retinoid
- Use at night retinoids are sensitive to sunlight and can degrade when exposed to UV rays
- Cleanse and dry the skin before applying retinoids, cleanse your face thoroughly, and ensure that your skin is dry. This helps the retinoid to absorb and reduces the risk of irritation
- Follow with moisturiser retinoids can cause dryness to your skin, so it is best to follow up with a moisturiser to help hydrate and soothe the skin
- Wear sunscreen retinoids can increase the skin's sensitivity to sunlight, making it more prone to sunburn and damage. It is therefore important to wear sunscreen daily to protect your skin from harmful UV rays
Side effects and other concerns
The main side effects to look out for when using retinoids include skin irritation, redness, peeling, and dryness. These side effects are usually temporary and can be managed by gradually introducing retinoids into the skincare routine and using moisturisers to alleviate dryness. However, individuals with extremely sensitive skin may need to consult a dermatologist to find the most suitable retinoid formulation.
In addition, retinoids should be avoided during pregnancy and breastfeeding, as they can potentially harm the baby's development or transfer through breast milk. It is therefore recommended to consult with a healthcare professional before using retinoids if you are planning to become pregnant.16
Retinoids have been shown to be effective in reducing wrinkles and fine lines, as well as improving the overall texture and tone of the skin. Their ability to increase cell turnover, stimulate collagen production, and protect against sun damage makes them a valuable tool in the fight against ageing. However, it is important to choose the appropriate retinoid formulation and to be aware of potential side effects. By incorporating retinoids into a comprehensive skincare routine, you can take proactive steps towards achieving a more youthful and radiant skin.
- Zasada M, Budzisz E. Retinoids: active molecules influencing skin structure formation in cosmetic and dermatological treatments. Postepy Dermatol Alergol [Internet]. 2019 Aug [cited 2023 Jul 14];36(4):392–7. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6791161/.
- Szymański Ł, Skopek R, Palusińska M, Schenk T, Stengel S, Lewicki S, et al. Retinoic acid and its derivatives in skin. Cells [Internet]. 2020 Dec 11 [cited 2023 Jul 14];9(12):2660. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7764495/.
- Mukherjee S, Date A, Patravale V, Korting HC, Roeder A, Weindl G. Retinoids in the treatment of skin aging: an overview of clinical efficacy and safety. Clin Interv Aging [Internet]. 2006 Dec [cited 2023 Jul 14];1(4):327–48. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2699641/
- Avila Rodríguez MI, Rodríguez Barroso LG, Sánchez ML. Collagen: A review on its sources and potential cosmetic applications. J Cosmet Dermatol [Internet]. 2018 Feb [cited 2023 Jul 14];17(1):20–6. Available from: https://onlinelibrary.wiley.com/doi/10.1111/jocd.12450.
- Yoham AL, Casadesus D. Tretinoin. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 [cited 2023 Jul 14]. Available from: http://www.ncbi.nlm.nih.gov/books/NBK557478/.
- Khalil NY, Darwish IA, Al-Qahtani AA. Chapter five - isotretinoin. In: Brittain HG, editor. Profiles of Drug Substances, Excipients and Related Methodology [Internet]. Academic Press; 2020 [cited 2023 Jul 14]. p. 119–57. (Profiles of Drug Substances, Excipients, and Related Methodology; vol. 45). Available from: https://www.sciencedirect.com/science/article/pii/S1871512519300202.
- Zasada M, Budzisz E. Randomized parallel control trial checking the efficacy and impact of two concentrations of retinol in the original formula on the aging skin condition: Pilot study. J of Cosmetic Dermatology [Internet]. 2020 Feb [cited 2023 Jul 14];19(2):437–43. Available from: https://onlinelibrary.wiley.com/doi/10.1111/jocd.13040.
- Jun SH, Kim H, Lee H, Song JE, Park SG, Kang NG. Synthesis of retinol-loaded lipid nanocarrier via vacuum emulsification to improve topical skin delivery. Polymers [Internet]. 2021 Jan [cited 2023 Jul 14];13(5):826. Available from: https://www.mdpi.com/2073-4360/13/5/826.
- Belyaeva OV, Adams MK, Popov KM, Kedishvili NY. Generation of retinaldehyde for retinoic acid biosynthesis. Biomolecules [Internet]. 2020 Jan [cited 2023 Jul 14];10(1):5. Available from: https://www.mdpi.com/2218-273X/10/1/5.
- Kwon HS, Lee JH, Kim GM, Bae JM. Efficacy and safety of retinaldehyde 0.1% and 0.05% creams used to treat photoaged skin: A randomized double-blind controlled trial. J Cosmet Dermatol [Internet]. 2018 Jun [cited 2023 Jul 14];17(3):471–6. Available from: https://onlinelibrary.wiley.com/doi/10.1111/jocd.12551.
- Kim J, Kim J, Lee YI, Suk J, Lee D, Lee JH. A pilot study evaluating the efficacy and safety of retinaldehyde‐loaded niosomes against mild‐to‐moderate acne. J of Cosmetic Dermatology [Internet]. 2021 Nov [cited 2023 Jul 14];20(11):3586–92. Available from: https://onlinelibrary.wiley.com/doi/10.1111/jocd.14478.
- Tetali B, Fahs FM, Mehregan D. Popular over-the-counter cosmeceutical ingredients and their clinical efficacy. Int J Dermatol [Internet]. 2020 Apr [cited 2023 Jul 14];59(4):393–405. Available from: https://pubmed.ncbi.nlm.nih.gov/31749194/.
- Sitohang IBS, Makes WI, Sandora N, Suryanegara J. Topical tretinoin for treating photoaging: A systematic review of randomized controlled trials. Int J Womens Dermatol [Internet]. 2022 Mar 25 [cited 2023 Jul 14];8(1):e003. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9112391/.
- Kaufman J, Callender V, Young C, Jones P, Wortzman M, Nelson D. Efficacy and tolerability of a retinoid eye cream for fine to moderate wrinkles of the periorbital region. J Drugs Dermatol [Internet]. 2022 Sep 1 [cited 2023 Jul 14];21(9):932–7. Available from: https://doi.org/10.36849/JDD.6815.
- Sadick N, Edison BL, John G, Bohnert KL, Green B. An advanced, physician-strength retinol peel improves signs of aging and acne across a range of skin types including melasma and skin of colo. J Drugs Dermatol [Internet]. 2019 Sep 1 [cited 2023 Jul 14];18(9):918–23. Available from: https://europepmc.org/article/med/31524348.
- Molin SC, Ruzicka T. Retinoids. In: Rustemeyer T, Elsner P, John SM, Maibach HI, editors. Kanerva’s Occupational Dermatology [Internet]. Berlin, Heidelberg: Springer; 2012 [cited 2023 Jul 14]. p. 1023–34. Available from: https://doi.org/10.1007/978-3-642-02035-3_91