About the author: John Su is a Weekly Contributing Writer to FutureDerm.com. John is an established skin care expert and aspiring dermatologist. He also runs a blog, The Triple Helix Liaison, dedicated to providing unbiased, meaningful, and insightful information about skin care. For his full bio, please visit our About page.
After an entire month, we’ve finally arrived at the most helpful part of this series. For each family of hydroxy acids, I will be reviewing and recommending three products from weakest to strongest potency. Keep in mind that I will only be doing a full review for the first product mentioned; there’s no need for this post to be 9-12 pages or columns long. I will be formatting this review the same way that I write formal reviews for my blog, The Triple Helix Liaison
Top 3 Products with Alpha Hydroxy Acids (AHAs)
1.) Paula’s Choice RESIST Daily Smoothing Treatment
(5% GA and 0.5% SA, pH = 3.5) ($25.95 for 1.7 oz)
This contains a high amount (about 1% based on the ingredient list) of palmitoyl oligopeptide, which has been shown to stimulate collagen production in human fibroblasts (1). Whether or not it can penetrate past the stratum corneum is unknown, but most likely it can because of its structural similarities to the Matrixyl family of peptides. There’s also high amounts of ceramide 2, which is a component of the epidermal barrier that increases water content, without adding too much emollience.
There are also high (>0.5%) amounts of several curcumin extracts (which have antioxidant and anti-inflammatory capacities), as well as epigallocatechin gallate, which is the most important polyphenolic component of green tea, and caffeic acid (a precursor to ferulic acid), which is a potent antioxidant and anti-inflammatory. Finally, there are moderate to low amounts of vitamin E, as well as the anti-inflammatory ingredients melon extract, bisabolol and allantoin, which will help offset any irritation that comes from the hydroxy acid contents.
In my opinion, the only way that this product could be improved, was if it included some L-ascorbic acid (maybe 5-7%), since the pH is appropriate and already contains stabilizers like vitamin E and ferulic acid (as caffeic acid). That would have netted this product a 100% rating. But alas, nothing’s perfect. Still, this is one of my Holy Grail products! Used every other day in my routine, it really just takes care of any dry, flaky skin, while leaving my face supple, lustrous, and smooth (without any irritation). Bravo!
Given the low, but still efficacious amount of glycolic acid (5%), this is an excellent everyday chemical exfoliant that I’d recommend to virtually every skin type. I really can’t think of one that wouldn’t benefit from this fantastic combination product! Not only does it contain GA, which will smooth and hydrate the skin, it also has a bit of SA (0.5%), which is enough for those who get that occasional breakout. Not to mention that you’re also getting a documented peptide, several antioxidants, water-binding agents, and anti-inflammatories thrown into the mix. And it’s all wrapped up in an elegant vehicular base that’s silky (due to the butylene glycol content) and light (thanks to a tad of cetyl alcohol)!
Perfect as the sole moisturizer for oily skin types, and can be easily layered with other products for dry sin types.
I give this product an A! Check the Product Review Rubric
for a full explanation on how I rate products.
Water, Glycolic Acid (AHA exfoliant), Cetyl Alcohol (thickener), Butylene Glycol (slip agent and penetration enhancer), Palmitoyl Oligopeptide (cell-communicating ingredient), Ceramide 2 (skin-identical ingredient), Tetrahydrodiferuloylmethane, Tetrahydrodemethoxydiferuloylmethane, Tetrahydrobisdemethoxydiferuoylmethane (anti-irritants/antioxidants derived from curcumin), Epigallocatechin Gallate, Caffeic Acid (antioxidants), Salicylic Acid (BHA exfoliant/anti-irritant), Disodium Lauriminodipropionate Tocopheryl Phosphates (vitamin E-based antioxidant), PEG-10 Rapeseed Sterol (fatty acid thickener), Cucumis Melo (Melon) Fruit Extract (antioxidant), Bisabolol, Allantoin (anti-irritants), Dimethicone, Cyclopentasiloxane, Cyclohexasiloxane, Dimethiconol (silicone slip agents/texture enhancers), Tribehenin (texture enhancer), Polysorbate 20 (emulsifier), C12-15 Alkyl Benzoate, PPG-14 Butyl Ether, PEG-40 Stearate, Sorbitan Stearate (thickeners), PVM/MA Decadiene Crosspolymer, Polyacrylamide (film-forming agents), Disodium EDTA (stabilizer), C13-14 Isoparaffin (solvent), Laureth-7 (emulsifier), Sodium Hydroxide (pH adjuster), Caprylyl Glycol (preservative), Ethylhexylglycerin (skin-conditioning agent), Hexylene Glycol (solvent), Phenoxyethanol (preservative).
2.) Olay Regenerist Night Resurfacing Elixir
(8-10% GA, pH = 3.8) ($31.99 for 1.7 oz):
With its slightly higher acid concentration and pH, this is slightly more potent than the RESIST Daily Treatment. It has a marginally more emollient base, due to the high glycerin content, but can still be used for all skin types. The other ingredients present, while not as impressive as the RESIST Daily, are still very good. They include moderate amounts of palmitoyl pentapeptide-4 or Matrixyl, which has been shown to improve photodamaged skin (2), as well as vitamin B5 (a humectant), and the green tea and grape seed extracts (both antioxidants). Overall, it’s quite excellent. Score: A
3.) Paula’s Choice RESIST Weekly Resurfacing Treatment (10% GA, pH = 3.5) ($28.95 for 2 oz):
At 10%, this can be a bit too potent and irritating for daily use. This is further exemplified due to the liquid vehicular base (water, butylene glycol, and a penetration enhancer methylpropanediol), that allows the GA to directly interact with the skin, with little to no chance of occlusion. There are many well-documented beneficial ingredients that would take too long to list and describe. But given the liquid base, they (the antioxidants) are most likely irrelevant because such compounds are easily oxidized in water alone. It doesn’t help that the packaging, which is the best that it can be for a liquid/toner base, allows air to easily reach the product. However, their presence is still good, and I’ll take “some benefit” over “no benefit” any day. There are also several anti-inflammatories that once again, are in place to offset the irritation potential of GA. This can be used by all skin types except the most sensitive and is overall, one of the best available on the market today. Score: 96.7%; A
Top 3 Products with Salicylic Acid (SA)
1.) Clinique Mild Clarifying Lotion
(0.5% SA, pH = 2.9) ($16- for 6.7 oz):
This is a slightly viscous toner that’s appropriate for those who don’t really deal with breakouts; perhaps just the occasional blackheads and whiteheads. Or for those who are sensitive to SA, but still want the benefits. This product contains some water-binding agents such as arginine and millet seed extract. Overall, it’s a mundane but still effective formula for select users. Plus the price is pretty good. Score: 80.0%; B-
2.) Neutrogena Oil-Free Acne Stress Control 3-In-1 Hydrating Acne Serum
(2% SA, pH = 3.4) ($5.99 for 2 oz):
In a silky lotion-gel base, this product is excellent as a moisturizer for those with oily skin types. Its primary occlusive agents are all silicones and therefore, form a breathable, but water-impermeable layer. This also contains moderate amounts of the calming cucumber and vitamin B5 compounds, as well as the antioxidant green tea. For a drugstore product, this is excellent. And this is completely irrelevant, but it smells SO good. Score: 90.0%; A-
3.) Paula’s Choice CLEAR Extra Strength Acne Relief Exfoliating Toner
(2% SA, pH = 3.2) ($18.95 for 4 oz):
This is the most potent OTC SA treatment that I could find. While not containing many other “beneficial” ingredients; it only has a tiny bit of green tea; this liquid SA exfoliant is fantastic! Just like with the RESIST Weekly Treatment, the liquid base allows the SA to penetrate the skin without any occlusion or resistance. Furthermore, because of the presence of the same penetration enhancer methylpropanediol, the SA not only penetrates more deeply, but can do so for a longer period of time. SA, partly because it’s lipid soluble nature, needs a vehicle that’s also lipid-soluble and doesn’t evaporate quickly. Once the vehicle becomes volatile (evaporates), SA’s capacity to penetrate and function becomes largely compromised as seen in SA chemical peels, where a white precipitate of SA will form, signifying that exfoliation is no longer occurring. That’s why SA chemical peels don’t need to be neutralized, unlike GA. So the methylpropanediol (which has a slightly greasy texture) is the ideal partner to SA because it allows the latter to keep exfoliating, without getting in the way via occlusion. This is another Holy Grail product. Win! Score: 96.7%; A
Products with Lipohydroxy Acid (LHA)
Unfortunately, I couldn’t find any products that were worth mentioning. Most of the ones that I encountered had at least one glaring negative or unknown aspect that couldn’t be overlooked. Some had too high pH values or unknown ones, while others had too low concentrations or contained high amounts of alcohol. Some were also included in cleansers, which I typically don't recommend. Cleansers don’t stay on the skin long enough to allow for adequate exfoliation. Anyways, every product I looked up had at least one or a combination of these issues so again, I cannot recommend any of them. We’ll just have to wait until more products start featuring this promising ingredient!
Top 3 Products with Polyhydroxy Acids (PHAs)
1.) Clinique Turnaround Concentrate Radiance Renewer
(~2-5% LBA, pH 3.6) ($49.00 for 1 oz):
This contains lactobionic acid, which while less studied than gluconolactone (GL), looks promising. However, this product is more appropriate for those who are looking for very gentle exfoliation and brightening of the skin, as this also contains high amounts of the mulberry extract, which has been shown to lighten the skin by inhibiting the tyrosinase enzyme (like most lighteners), as well as the oxidation of L-DOPA (dihydroxyphenylalanine) (3). It has also been shown that PHAs like simpler AHAs, work synergistically with various lighteners (4). This also contains other well-documented ingredients such as grape extract (antioxidant), and the wheat germ and rice bran extracts (humectants), as well as a tiny amount of SA. Overall, this is a great product for those who are looking for a brightening serum/light moisturizer who have not had good results with AHAs and lighteners such as hydroquinone. Score: 93.3%; A
2.) Exuviance Matte Perfection (10% GL and Mandelic Acid (MA), pH = 3.7) ($31.90 for 1 oz):
While not containing any beneficial ingredients like antioxidants, etc. this does deserve attention because its vehicular base is very light and appropriate for even the most oily of skin types. Mandelic acid, while not previous mentioned before, is an AHA that appears to function like a less-irritating GA (5). I also recommended this because it’s one of the few Exuviance products that doesn’t use the pH balancer triethanolamine, which due to its high alkalinity has the potential to generate nitrosamines, which are carcinogenic. Score: 83.3%; B
3.) Neostrata Bionic Lotion, 15 PHA (12% GL and 3% LBA, pH 3.8) ($35.00 for 3.4 oz):
Just like the Exuviance product, this doesn’t contain anything really exciting other than the PHAs. However, I recommended this because of the high concentrations of two LHAs and the price per ounce is excellent! Again, this product was also recommended because it doesn’t contain any triethanolamine. This particular formula is suited for those with normal to dry skin types. Score 90.0%; A-
I realize that there are a million and one well-formulated products that contain AHAs and SA, such as the ones available from Alpha Hydrox, Glytone, and PCA Skin. However, I tried to find products that go above and beyond the baseline requirement of having just hydroxy acids.
Keep in mind that I didn’t cite a lot of the stuff I said about various ingredients, just because if I were to cite every ingredient that I mentioned and explain their differing mechanisms of action, that would take a year and a day, or two! So in good faith, I assuming that you guys will believe me when I state something. Of course, if you would like more information or documentation, or if you would like to see a more detailed review of a product, let me know on my blog or down below in the comments section.
Well, that wraps up our FOUR part discussion about hydroxy acids! Phew! If you’d like to nominate a topic for next week’s post, please let me know!
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