Over-Night Biological Peel

by Kiehl's  
$46 - 1.7 fl. oz.
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Skin Care > Retinol Products > Exfoliants
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Over-Night Biological Peel is supposed to be as potent as a 10% glycolic acid product, but it contains no alpha hydroxy acids, or beta hydroxy acid for that matter. Instead, this water- and silicone-based fluid contains urea, which is indeed an exfoliant, albeit a far less sexy version than AHAs or BHA because it’s derived from urine (though most cosmetic companies use a synthetic version). Urea definitely has exfoliating and water-binding properties when used on skin, and unlike AHAs and BHA, its efficacy is not pH-dependent. Much as AHAs do, it can cause a stinging sensation on application. Urea can be beneficial for those with dry skin because, although the manner in which it works isn’t fully understood, it has proven very effective at reducing moisture loss from the epidermis (Source: Dry Skin and Moisturizers Chemistry and Function, Loden & Maibach, 2000, pages 235–236). Kiehl’s ingredient list also points to HEPES as an enzyme activator. However, this ingredient (hydroxyethylpiperazine ethane sulfonic acid) functions as a buffering agent, which should help reduce any potential irritation from the urea. Although this peel is pricey and not necessarily superior to an AHA (or BHA) product, it is nevertheless a novel approach to exfoliating skin if you’re curious to try something different, or if your skin has not responded favorably to AHA products.

Stimulates skin’s biological exfoliation process-for noticeably smoother, more even and vibrant skin by morning. With first overnight application, skin texture is noticeably softer. Diminishes the visible effects of free-radical and photo-damage over time. Helps reduce the appearance of dark spots and hyperpigmentation with continued use. Performs as well as a potent 10% Glycolic Acid leave-on chemical peel-as prescribed by a dermatologist.

Water, Cyclopentasiloxane, Urea, Hydroxyethylpiperazine Ethane Sulfonic Acid, Glycerin, C12-15 Alkyl Benzoate, Propylene Glycol, Cetyl PEG/PPG-10/1 Dimethicone, Bis-PEG/PPG-14/14 Dimethicone, Triethanolamine, Phenoxyethanol, Sodium Chloride, Sodium Hyaluronate, Sodium PCA, Methylparaben, Propylparaben, Ethylparaben, Isobutylparaben, Butylparaben

This line has been around for quite some time, and has its origins in a family-owned pharmacy based in New York City. Perhaps its neighborly beginnings with a big-city heritage are what propelled Kiehl's to its long-standing status as a popular product line. Considering that Kiehl's doesn't advertise (at least not in the traditional sense, though their products get frequent press), their brand identity and status in the minds of consumers are impressive.

What gets lost in all the fashion magazine hype and company claims of "excellence" and "quality ingredients" is that almost all of the Kiehl's products hardly warrant excitement or even mild enthusiasm. Most of them are surprisingly ordinary, with a dusting of natural ingredients almost always at the very end of the ingredient list, well after the preservatives. That amounts to little more than a token attempt to make the products appear more natural to those who want to believe a plant or vitamin must somehow be better for the skin than something that sounds more chemical. Nevertheless, that token amount is enough to allow Kiehl's to brag about how its products nourish the skin or are more environmentally friendly, when they're not.

Aside from the allure of the natural, this line consists of totally ordinary and often completely unnatural ingredients. More disheartening for skin is that many of the ingredients are of questionable benefit for those with sensitive, oily, or blemish-prone skin. In some instances product ingredients are irritating for any skin type, while half of the sunscreen products are a serious problem for reliable sun protection. If you can't resist the allure of Kiehl's, just know that the product assembly will work best for those with dry to very dry skin and that, for the money, most of the formulas aren't knock-your-socks-off thrilling.

Note: Kiehl's is categorized as a brand that tests on animals because its products are sold in China. Although Kiehl's does not conduct animal testing for its products sold elsewhere, the Chinese government requires imported cosmetics be tested on animals, so foreign companies retailing there must comply. This requirement is why some brands state that they don’t test on animals “unless required by law.” Animal rights organizations consider cosmetic companies retailed in China to be brands that test on animals, and so does the Paula’s Choice Research Team.

For more information about Kiehl's, owned by L'Oreal, call (800) 543-4572 or visit www.kiehls.com.

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About the Experts

Paula Begoun is the best-selling author of 20 books on skin care and makeup. She is known worldwide as the Cosmetics Cop and creator of Paula's Choice. Paula's expertise has led to hundreds of appearances on national and international television including:

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The Paula's Choice Research Team is dedicated to helping you find the absolute best products for your skin, using research-based criteria to review beauty products from an honest, balanced perspective. Each member of the team was personally trained by Paula herself.

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