AHAs, BHAs, and PHAs
Most of these face acids fall into three main categories, such as the Alpha Hydroxy Acids (AHAs), Beta Hydroxy Acids (BHAs), and Polyhydroxy Acids (PHAs).
Alpha Hydroxy Acids (AHAs)
AHAs are water-soluble organic compounds derived from various natural sources. These acids, when applied topically to the skin's surface, encourage exfoliation of keratin protein, dirt and scales in the stratum corneum, allowing newer, healthier cells to emerge through.
The acid also boosts a plumping effect, promotes collagen production in fibroblasts, and improves the quality of elastic fibers in the skin. This results in an improved radiance and texture (fine lines), which can be observed with weeks of consistent use.
AHA-based face acids are often used for conditions such as ichthyosis, dry skin, various forms of keratoses, and follicular hyperkeratosis.
Beta Hydroxy Acids (BHAs)
Beta hydroxy acids (BHAs), most notably salicylic acid, are lipid-soluble compounds that possess the unique ability to penetrate through the sebaceous lipid layer within pores and follicular structures.
These acids are particularly effective for individuals with oily or acne-prone skin because they can reduce sebum oxidation and comedone formation while providing notable anti-inflammatory benefits. This potentially helps calm active breakouts and redness associated with inflammatory acne lesions.
Polyhydroxy Acids (PHAs)
Polyhydroxy acids (PHAs) are a third type of hydroxy acid and have a larger molecular structure. Due to this, compounds like gluconolactone and lactobionic acid provide gentler exfoliation, naturally slowing their penetration rates into the epidermis.
PHAs also possess humectant and antioxidant properties, which make them particularly suitable for individuals with sensitive or compromised skin barriers who cannot tolerate traditional AHAs or BHAs.
Lactic, Glycolic, Salicylic, and Mandelic Acid
Let's have a look at some of the common AHAs and BHAs used in skincare:
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Lactic Acid
This is an AHA, originally derived from sour milk, which functions as both an effective exfoliant and a humectant. It is ideal for reactive skin that experiences irritation with more aggressive acids.
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Glycolic Acid
It is famous for penetrating into the epidermis most effectively, reaching deeper layers than larger AHA molecules. GA is known for its anti-aging properties, potentially refining your skin’s texture.
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Salicylic Acid
This beta hydroxy acid possesses anti-inflammatory properties and effectively cleans the pores and clogged comedones, making it a good choice for those with blackheads, whiteheads, or oily-prone concerns.
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Mandelic Acid
Mandelic acid is an AHA derived from bitter almonds. It features a larger molecular structure than glycolic or lactic acid, resulting in the most gradual penetration among commonly used AHAs. You may use the topical agent for addressing hyperpigmentation and uneven tone, especially for oily skin types.