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Anti-inflammatory, exfoliating, antiacne, depigmenting, moisturizing

Important Chemical Components:

Mostly carbon, hydrogen, and oxygen

Molecular formulas:

  • Citric acid: C6H8O7

  • Gluconolactone C6H10O6

  • Glycolic acid: C2H4O3

  • Lactic acid: C3H6O3

  • Malic acid: C4H6O5

  • Mandelic acid: C8H8O3

  • Phytic acid: C6H18O24P6

  • Salicylic acid: C7H6O3

  • Tartaric acid: C4H6O6

Origin Classification:

Acids are all found in natural sources, but are synthesized in the laboratory for use in chemical peels and other products.

Personal Care Category:

Antiaging, exfoliant, brightening, antiacne, moisturizer

Recommended for the following Baumann Skin Types:

DRNW, DRPW, DSNW, DSPW, ORNW, ORPW, OSNW, and OSPW. Hydroxy acids are used in all Baumann Skin Types but the choice of hydroxy acid depends on the individual skin type. All of the acids discussed in this chapter are useful in wrinkle-prone skin types. Acids used for acne indications are discussed in the acne section of this text.


Found in plants but also manufactured in the laboratory, α-hydroxy acids (AHAs), polyhydroxy acids (PHAs), and β-hydroxy acid (BHA) are naturally-occurring organic acids that induce exfoliation and accelerate the cell cycle. The plant source depends on the type of hydroxy acid. There are several types of AHAs: citric acid from citrus fruits; glycolic acid from sugar cane, grapes, sugar beets, and Virginia creeper leaves; malic acid from fruits such as cherries and apples; mandelic acid from bitter almond; lactic acid from dairy as well as fermented vegetables and fruit; phytic acid from rice; and tartaric acid from grapes.1

PHAs, also known as polyhydroxy bionic acids (PHBAs), include gluconolactone and lactobionic acid.2 They were developed to deliver the antiaging efficacy of AHAs without the irritation or increased vulnerability to ultraviolet (UV) radiation due to their antioxidant effects (Table 82-1).

TABLE 82-1Pros and Cons of Hydroxy Acids

BHA, also known as salicylic acid (SA), is found in willow bark, almonds, water chestnuts, peanuts, and some fruits and vegetables. There is only one type of BHA, as compared to the several types of AHA and PHA. BHA can also be produced in the laboratory from phenylalanine or by hydrolysis of aspirin (acetylsalicylic acid) or oil of wintergreen (methyl salicylate).


Cleopatra was said to have routinely bathed in sour ...

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