Signs of skin aging: what are the effects of mandelic acid?

Would promote the production of new collagen and elastin.

Stimulates the secretion of sebum.

Reduces the appearance of wrinkles.

Would improve the skin's elasticity.

Inevitable, aging affects the entire body and the skin is the most exposed to the effects of time. Overall, skin aging is characterized by a degradation of all the skin's components. The mature epidermis then exhibits numerous characteristics, which can intensify with age and environmental factors.

• Loss of Radiance: Mature skin often gives the impression of a blurred complexion, which can be attributed to an accumulation of old cells on the skin's surface. As it ages, cellular renewal slows down. Additionally, with age, the epidermis receives fewer nutrients and oxygen due to a slowdown in blood flow.

• Loss of elasticity, skin sagging: With age, the skin loses its ability to return to its original shape when pinched or stretched, becoming "slack" with visible sagging. This property is made possible thanks to elastin, a protein present in the dermis, which contributes to the skin's flexibility. However, over time, the amount of elastin gradually decreases to such an extent that mature skin contains five times less elastin than "young" skin.

• Loss of volume: cheekbones, eye contours... certain areas of the face are prone to a loss of density, causing the skin to sag. This loss of bounce is due to dermal water loss with a decrease in the natural content of hyaluronic acid, muscle atrophy, melting of subcutaneous adipose tissue, and loss of bone density. It is exacerbated by an alteration in the structure of the dermis, which is primarily composed of collagen and elastin.

• Wrinkles: primarily around the eye contour and corners of the mouth, grooves form and settle on the face. Among these wrinkles, some are static, others are dynamic. Various mechanisms underlie their appearance: weakening and oxidation of collagen structures, excessive contraction of facial muscles, repeated exposure to the sun, etc.

• Age Spots : more visible and numerous, this common form of hyperpigmentation most often occurs in people over the age of 40. They are caused by frequent oxidation of skin cells which exacerbates skin aging. Excessive and repeated exposure to oxidants such as the sun can induce an excess of melanin.

To enhance skin quality, making it denser and more elastic, several solutions exist, including chemical peels. Their purpose? They help delay the effects of skin aging, as they can promote cell proliferation and metabolic activity, thereby boosting the production of collagen and elastin fibers, thanks to the exfoliating action they induce. As a bonus, wrinkles are "smoothed out", sun spots are faded, and the complexion is brightened.

Themandelic acid does everything that other alpha-hydroxy acids (AHA) do, and even more. What sets it apart from other fruit acids? It's its antibacterial, anti-inflammatory, antioxidant, and gentle action. Indeed, most publications report its benefits in the treatment of acne and hyperpigmentation, without the risk of redness or irritation. In its natural state, mandelic acid is derived from the bitter almond, a non-edible fruit of the wild almond tree.

Mandelic acid has a larger molecular structure than other popular AHAs: nearly twice as large as that of glycolic acid. This greater size means it is absorbed by the skin more slowly and does not penetrate as deeply into the epidermis when applied. This makes it gentler, and individuals with sensitive or acne-prone skin have fewer issues with mandelic acid than with other AHAs.

It is proven that mandelic acid exfoliates the skin. The observed effects depend on the concentration of mandelic acid in the skincare product. It is generally used in skincare at a concentration of 10% or less. However, doctors can prescribe or apply, as part of a dermatologically controlled chemical peel for example, products with a higher concentration of active ingredients (> 10%), yielding more "dramatic" effects.

In a study, CULBERTSON E. & al. evaluated the effects of a mandelic acid skincare treatment on improving the quality of mature skin, characterized by its extensibility property. This single-center clinical study of four weeks was conducted on 24 patients aged 42 to 68 years presenting with skin laxity and fine lines on the eyelids. They were instructed to apply a mandelic acid-based treatment on one side of the face twice a day, specifically a serum with 6% mandelic acid during the day and a 4% mandelic acid night cream in the evening. The viscoelastic properties of the skin of the lower eyelids were evaluated using a Cutometer, a tool designed to assess the effectiveness of a treatment by measuring the biomechanical properties (viscoelasticity) of the upper layers of the epidermis.

Researchers have found that the viscoelasticity of the skin under the eyes can be significantly improved by using mandelic acid twice a day for 4 weeks. Similarly, an increase in skin firmness has also been observed. Subjectively, an improvement in the appearance of fine lines at the outer corner of the eyes has also been demonstrated after four weeks of topical application. Although it was not directly tested with the Cutometer, it appears that improvements on other treated areas of the face and neck have been observed. The result? Firmer, more elastic, and less wrinkled skin in the orbital area. Researchers suggest that this phenomenon is explained by the ability of mandelic acid to stimulate dermal fibroblasts to produce more collagen, elastin, and glycosaminoglycans in the papillary dermis through an indirect and still unknown mechanism.

From what perspective should this article be considered?

Although improvements have been observed in skin elasticity, firmness does not show a significant difference. The small number of volunteers is also a factor to consider. Furthermore, it would be beneficial to test on other areas of the face prone to skin sagging. Lastly, it would also be necessary to evaluate how long the effect is maintained over time.

Mandelic acid also reportedly helps to diminish the appearance of wrinkles and fine lines. By accelerating the natural exfoliation of damaged outer layers of the epidermis, it also speeds up skin regeneration. This thinning of the stratum corneum not only improves the texture and radiance of the skin, but also gradually, continuously, and repeatedly reduces the appearance of fine lines. In addition, mandelic acid has been shown to stimulate the production of elastin and collagen according to a study. It also stimulates or balances sebum production, which helps maintain skin hydration when it is dry or damaged. This improvement in wrinkles and fine lines can be observed in patients with Fitzpatrick skin types I to VI, without the risk of post-inflammatory hyperpigmentation, erythema, and the formation of any other adverse effects on the epidermis that accompany treatments with glycolic acid.

• TAYLOR M. B. Summary of mandelic acid for the improvement of skin conditions. Cosmetic Dermatology (1999).

• ROTSZTEJN H. & al. Influence of azelaic and mandelic acid peels on sebum secretion in aging women. Advances in Dermatology and Allergology (2013).

• CULBERTSON E. J. & al. Effects of topical mandelic acid treatment on facial skin viscoelasticity. Quick Communication (2018).