Sun spots, pregnancy masks, post-acne brown marks... they all refer to a form of hyperpigmentation. They alter the uniformity of the complexion and can be unwanted, even though they are benign. Fortunately, by adopting the right active ingredients, it is possible to reduce them and AHAs are a good remedy. Is this also the case with mandelic acid?
Hyperpigmentation: Can Mandelic Acid Fade the Appearance of Brown Spots?
Summary
Published on March 1, 2024, by Stéphanie, PhD, Doctorate in Life and Health Sciences — 5 min of reading
Themes:
Where Do Pigmentation Spots Come From?
Known under different names, hyperpigmentation is the appearance of small areas that are darker than the rest of the skin. It comes from an increase in the production of melanin (melanoderma), the protective brown pigment of the skin, and its accumulation on certain areas of the body: face, hands, neckline especially. Exposure to radiation, hormonal disorders, genetic predisposition, skin aging... there are several factors that lead to this phenomenon: free radicals, sun exposure, hormonal variation, inflammation, pollution... Under the term "brown spots" are hidden several typologies according to their origin.
Sun spots: generally appearing around the age of 40, these more or less round-shaped spots, present in varying numbers on the skin, are common on fair skin and generally affect the areas most exposed to the sun, such as the back of the hands, the neckline or the face. They are induced by overexposure to the sun or artificial UV light.
Melasma: common in women, this type of hyperpigmentation takes the form of pigmented patches that are often symmetrical and more or less limited, generally distributed on the forehead, cheeks, upper lip and temples. It mainly affects women with a darker phototype. Pregnancy, taking the contraceptive pill or hormone replacement therapy... This type of spot is linked to a hormonal change: an increase in the levels of female hormones that stimulate the production of melanin. A genetic predisposition has also been added as a responsible factor.
Post-inflammatory hyperpigmented marks: these brown spots appear following skin inflammation (acne, burns, wounds, eczema, etc.) during the healing process. The pro-inflammatory molecules sometimes stimulate the melanocytes, leading to an increase in the production of melanin.
Can You Reduce Hyperpigmented Areas With Mandelic Acid Exfoliation?
Mandelic acid is an aromatic compound in the alpha hydroxy acid (AHA) family, comparable to glycolic acid and lactic acid. It comes from the bitter almond, a variety of the wild almond tree. Exfoliating, antioxidant, anti-microbial, anti-inflammatory... Thanks to its numerous properties, mandelic acid is used in the composition of various skin care products: it is notably an excellent treatment for acne and various skin inflammations. In addition, it is appreciated for its gentle action: its high molecular weight makes it gentle compared to other fruit acids.
In addition to improving acne and the signs of skin aging, some studies have also shown the effectiveness of mandelic acid in reducing the appearance of pigmentation spots, particularly melasma. A 1999 study in which subjects used a lotion with 10% mandelic acid found that it reduced hyperpigmentation in melasma patients by 50% after one month of treatment. In another 2016 study, researchers evaluated the therapeutic efficacy of glycolic acid (35%) and salicylic-mandelic acid (20% salicylic acid/10% mandelic acid) peels in Indian patients diagnosed with melasma. It revealed that both types of acid were equally effective in reducing the appearance of melasma, with a better tolerance for salicylic-mandelic acid, after 12 weeks of treatment. The same observations were made on post-inflammatory hyperpigmentation in a 2008 study.
The key point? By exfoliating the skin, mandelic acid helps to gently peel away the melanin pigmented cells that have risen to the surface of the skin, in addition to promoting the skin's cellular renewal. Thus, these studies have demonstrated its effectiveness in evening out skin tone and making the skin more uniform by performing a semi-regular dermal exfoliation with mandelic acid.
Sources
TAYLOR M. B. Summary of mandelic acid for the improvement of skin conditions. Cosmetic Dermatology (1999).
SARKAR R. & al. Glycolic acid peels versus salicylic–mandelic acid
peels in active acne vulgaris and post-acne scarring and hyperpigmentation: a comparative study. American Society for Dermatologic Surgery (2008).GUPTA C. & al. Comparative evaluation of efficacy and tolerability of glycolic acid, salicylic acid, mandelic acid, and phytic acid combination peels in melasma. Dermatologic Surgery (2016).
