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Skin science article

Haruharu Wonder Centella 3% PHA Gentle Liquid Exfoliating Serum Versus Paula's Choice Skin Perfecting 6% Mandelic Acid + 2% Lactic Acid Liquid Exfoliant

Haruharu Wonder Centella 3% PHA Gentle Liquid Exfoliating Serum Versus Paula's Choice Skin Perfecting 6% Mandelic Acid + 2% Lactic Acid Liquid Exfoliant This smoothing exfoliator is formulated around Gluconolactone and Centella Asiatica Extract to refine skin

Haruharu Wonder Centella 3% PHA Gentle Liquid Exfoliating Serum Versus Paula's Choice Skin Perfecting 6% Mandelic Acid + 2% Lactic Acid Liquid Exfoliant

This smoothing exfoliator is formulated around Gluconolactone and Centella Asiatica Extract to refine skin texture and calm redness.

This smoothing exfoliator is formulated around Mandelic Acid and Lactic Acid to refine skin texture and brighten dull-looking skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Citrus Aurantium Dulcis Fruit Water

Gluconolactone

Centella Asiatica Extract

Asiatic Acid

Asiaticoside

Madecassic Acid

Madecassoside

Ectoin

Sodium Hyaluronate

Saccharomyces/Xylinum/Black Tea Ferment

Pueraria Lobata Root Extract

Pinus Palustris Leaf Extract

Ulmus Davidiana Root Extract

Oenothera Biennis Flower Extract

1,2-Hexanediol

Arginine

Ethylhexylglycerin

Pentylene Glycol

Caprylyl Glycol

Butylene Glycol

Water, Citrus Aurantium Dulcis Fruit Water, Gluconolactone, Centella Asiatica Extract, Asiatic Acid, Asiaticoside, Madecassic Acid, Madecassoside, Ectoin, Sodium Hyaluronate, Saccharomyces/Xylinum/Black Tea Ferment, Pueraria Lobata Root Extract, Pinus Palustris Leaf Extract, Ulmus Davidiana Root Extract, Oenothera Biennis Flower Extract, 1,2-Hexanediol, Arginine, Ethylhexylglycerin, Pentylene Glycol, Caprylyl Glycol, Butylene Glycol

2,3-Butanediol

Mandelic Acid

Lactic Acid

Sodium Hydroxide

Myrica Cerifera Fruit Extract

Akebia Quinata Stem Extract

Prunus Lannesiana Flower Extract

Lactobacillus Ferment Lysate

Saccharomyces Lysate

Achillea Millefolium Extract

Saccharide Isomerate

Hydroxyacetophenone

Sodium Phytate

Xanthan Gum

Citric Acid

Sodium Citrate

Sodium Benzoate

Water, 2,3-Butanediol, Mandelic Acid, Lactic Acid, Sodium Hydroxide, Myrica Cerifera Fruit Extract, Akebia Quinata Stem Extract, Prunus Lannesiana Flower Extract, Lactobacillus Ferment Lysate, Saccharomyces Lysate, Achillea Millefolium Extract, Saccharide Isomerate, Arginine, Hydroxyacetophenone, Butylene Glycol, Sodium Phytate, Pentylene Glycol, Xanthan Gum, Citric Acid, Sodium Citrate, 1,2-Hexanediol, Caprylyl Glycol, Sodium Benzoate

Reviews

Alternatives

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

1,2-Hexanediol is a synthetic liquid and another multi-functional powerhouse.

It is a:

Humectant, drawing moisture into the skin

Emollient, helping to soften skin

Solvent, dispersing and stabilizing formulas

Preservative booster, enhancing the antimicrobial activity of other preservatives

Arginine is a semi-essential amino acid. This just means our bodies can product a bit on its own, but sometimes needs a little boost from food sources.

It is a part of your skin's natural moisturizing factor (NMF), or the water-loving molecules in your outermost layer of skin (stratum corneum) that keeps everything hydrated and happy.

Here's an interesting thing about Arginine: your skin converts it into urea through the Krebs-Henseleit urea cycle. Urea is one of the most effective humectants your skin naturally produces.

A clinical study showed applying 2.5% arginine hydrochloride to atopic dermatitis skin showed significant urea levels in the stratum corneum and improved moisture in just four weeks.

Arginine is also a precursor to nitric oxide; nitric oxide improves microcirculation and supports wound healing and collagen synthesis.

One study found that an amino acid complex containing Arginine reduced skin irritation, improved hydration, and accelerated skin repair in clinical / in-vivo studies.

Arginine itself is an amino acid and not a fatty acid, oil, or ester. On its own, it's not a direct food source for Malassezia, or the yeast that causes fungal acne.

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.

Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.

Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.

Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).

Pentylene Glycol (1,2-pentanediol) is a multitasking little diol with three main roles in a formula:

Research on alkanediols (the family pentylene glycol belongs to) show they work by disrupting microbial cell membranes. This disruption helps the primary preservative system in a product work more effectively at lower doses.

On the safety side, the Cosmetic Ingredient Review Expert Panel has concluded this ingredient to be safe as used in current cosmetic practices + concentrations.

Typical use levels in a formula run about 1-5%.

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.

You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!

Similar Comparisons

The reference edit

Ingredients, questions
& further reading.

Connected source records selected through this article’s public topic index.

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Formula cabinet

Ingredients & structured notes

Ingredient index

Ingredients Explained

  1. 01These ingredients are found in both products.
  2. 02Ingredients higher up in an ingredient list are typically present in a larger amount.
  3. 03Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.
  4. 04Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.
  5. 05However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.
  6. 06Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.
  7. 07In skincare formulas, citric acid can:
  8. 08While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.
  9. 09Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.
  10. 10Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger.
  11. 11However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's…
  12. 12Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  13. 13Topically, glycerin does several things at once:
  14. 14Your skin makes glycerin on its own (mostly from sebaceous oil breakdown) and shuttles it to your outermost layer of skin, or your epidermis, via aquaporin-3.
  15. 15Aquaporin-3 is a transporter that is essential for normal skin hydration, elasticity, and repair. Interestingly, mice lacking in AQP3 have dry and less elastic skin that can be fully corrected with glycerin.
  16. 16This ingredient is non-irritating, plays well with almost every ingredient, and works across all skin types. Typical use is anywhere between 3-10% but can go up to 79% in some leave-on products.
  17. 17Just know very high concentrations (>40%) can feel tacky in low humidity.
  18. 18Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  19. 19Niacinamide is a multitasking form of vitamin B3 that strengthens the skin barrier, reduces pores and dark spots, regulates oil, and improves signs of aging.
  20. 20And the best part? It's gentle and well-tolerated by most skin types, including sensitive and reactive skin.
Source · skinsort.com
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