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Face Reality Skincare 5% L-Mandelic Serum Versus Paula's Choice Skin Perfecting 6% Mandelic Acid + 2% Lactic Acid Liquid Exfoliant

Face Reality Skincare 5% L-Mandelic Serum Versus Paula's Choice Skin Perfecting 6% Mandelic Acid + 2% Lactic Acid Liquid Exfoliant This acne serum is formulated around Mandelic Acid and Lactic Acid to clear breakouts and refine skin texture. This smoothing exf

Face Reality Skincare 5% L-Mandelic Serum Versus Paula's Choice Skin Perfecting 6% Mandelic Acid + 2% Lactic Acid Liquid Exfoliant

This acne serum is formulated around Mandelic Acid and Lactic Acid to clear breakouts and refine skin texture.

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

Hamamelis Virginiana Water

Mandelic Acid

Alcohol

Lactic Acid

Butylene Glycol

PPG-3 Benzyl Ether Myristate

Alcohol Denat.

Niacinamide

Polyglyceryl-4 Caprate

Sodium Lactate

Xanthan Gum

Sodium PCA

Sodium Hyaluronate

Urea

Phenethyl Alcohol

Caprylyl Glycol

Potassium Sorbate

Water, Hamamelis Virginiana Water, Mandelic Acid, Alcohol, Lactic Acid, Butylene Glycol, PPG-3 Benzyl Ether Myristate, Alcohol Denat., Niacinamide, Polyglyceryl-4 Caprate, Sodium Lactate, Xanthan Gum, Sodium PCA, Sodium Hyaluronate, Urea, Phenethyl Alcohol, Caprylyl Glycol, Potassium Sorbate

2,3-Butanediol

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

Sodium Phytate

Pentylene Glycol

Citric Acid

Sodium Citrate

1,2-Hexanediol

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.

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).

Lactic Acid is another well-loved alpha hydroxy acid (AHA). It is gentler than glycolic acid but still highly effective.

Its main role is to exfoliate the surface of the skin by loosening the “glue” that holds dead skin cells together. Shedding those old cells leads to smoother, softer, and more even-toned skin.

Because lactic acid molecules are larger than glycolic acid, they don’t penetrate as deeply. This means they’re less likely to sting or irritate, making it a great choice for beginners or those with sensitive skin.

Like glycolic acid, it can:

Lactic acid also acts as a humectant (like hyaluronic acid). It can draw water into the skin to improve hydration and also plays a role in the skin's natural moisturizing factor (NMF) in the form of sodium lactate.

Studies show it can boost ceramide production to strengthen the skin barrier and even help balance the skin’s microbiome.

To get results, choose products with a pH between 3-4.

Lower strengths (5-12%) focus on surface exfoliation; higher strengths (12% and up) can reach deeper in the dermis (deeper, supportive layer) to improve skin texture and firmness over time.

Though it was originally derived from milk, most modern lactic acid used in skincare is vegan. It is made through non-dairy fermentation to create a bio-identical and stable form suitable for all formulations.

When lactic acid shows up near the end of an ingredient list, it usually means the brand added just a tiny amount to adjust the product’s pH.

Legend has it that Cleopatra used to bathe in sour milk to help reduce wrinkles.

Lactic acid is truly a gentle multitasker: it exfoliates, hydrates, strengthens, and brightens. It's a great ingredient for giving your skin a smooth, glowing, and healthy look without the harshness of stronger acids.

Read more about some other popular AHA's here:

Mandelic Acid is an alpha hydroxy acid (AHA).

Like other AHAs, it helps exfoliate the surface of the skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.

Mandelic acid helps with:

Due to it having a larger molecular size than glycolic acid, mandelic acid is able to penetrate the skin more slowly and evenly. This makes it gentler and less irritating, making it a great option for sensitive or beginner skin.

Despite being milder, mandelic acid is still an effective exfoliant that improves skin texture and tone over time.

What makes mandelic acid stand out from other AHAs? It has antibacterial and antioxidant properties.

These traits make it a great option for acne-prone or problem skin by reducing active breakouts and fading post-acne marks. Studies show that mandelic acid (especially when combined with salicylic acid) can significantly reduce pimples and hyperpigmentation while causing fewer side effects than stronger acids.

Mandelic acid is effective in concentrations of 5% and up with an ideal pH range of 3-4 for at-home use.

Like other AHAs, it’s important to wear sunscreen daily to protect your newly exfoliated skin.

However, unlike glycolic acid, mandelic acid is light-sensitive. Be sure your mandelic acid is packaged in opaque containers to ensure it stays stable and effective.

In short, mandelic acid is a gentle yet powerful AHA that exfoliates, brightens, and helps clarify skin while keeping irritation low. Its antibacterial action makes it especially beneficial for those with acne-prone, sensitive, or uneven skin, offering smoother, clearer, and more even-toned results over time.

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!

Xanthan gum is used as a stabilizer and thickener within cosmetic products. It helps give products a sticky, thick feeling - preventing them from being too runny.

On the technical side of things, xanthan gum is a polysaccharide - a combination consisting of multiple sugar molecules bonded together.

Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food products.

Similar Comparisons

The reference edit

Ingredients, questions
& further reading.

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

01

Formula cabinet

Ingredients & structured notes

Ingredient index

Paula's Choice Defense Antioxidant Pore PurifierIngredients explained

  1. 01Good old water, aka H2O. The most common skincare ingredient of all. You can usually find it right in the very first spot of the ingredient list, meaning it’s the biggest thing out of all the stuff that makes up the product.
  2. 02It’s mainly a solvent for ingredients that do not like to dissolve in oils but rather in water.
  3. 03Expand to read more
  4. 04Once inside the skin, it hydrates, but not from the outside - putting pure water on the skin (hello long baths!) is drying.
  5. 05One more thing: the water used in cosmetics is purified and deionized (it means that almost all of the mineral ions inside it is removed). Like this, the products can stay more stable over time.
  6. 06Propanediol is a natural alternative for the often used and often bad-mouthed propylene glycol. It's produced sustainably from corn sugar and it's Ecocert approved.
  7. 07It's quite a multi-tasker: can be used to improve skin moisturization, as a solvent, to boost preservative efficacy or to influence the sensory properties of the end formula.
  8. 08Butylene glycol, or let’s just call it BG, is a multi-tasking colorless, syrupy liquid. It’s a great pick for creating a nice feeling product.
  9. 09BG’s main job is usually to be a solvent for the other ingredients. Other tasks include helping the product to absorb faster and deeper into the skin (penetration enhancer), making the product spread nicely over the skin (slip agent), and attracting…
  10. 10It’s an ingredient whose safety hasn’t been questioned so far by anyone (at least not that we know about). BG is approved by Ecocert and is also used enthusiastically in natural products. BTW, it’s also a food additive.
  11. 11A nice odorless liquid used mainly as a superior solubilizer and efficacy booster for cosmetic active ingredients such as skincare bigshot vitamin C, self-tanning active DHA or the anti-acne gold standard, benzoyl peroxide.
  12. 12Other than that it can also be used in hair care products where it gives a longer-lasting and more uniform coloring. According to a manufacturer, it might even prevent the formation of split ends.
  13. 13A natural moisturizer that’s also in our skin
  14. 14A super common, safe, effective and cheap molecule used for more than 50 years
  15. 15Not only a simple moisturizer but knows much more: keeps the skin lipids between our skin cells in a healthy (liquid crystal) state, protects against irritation, helps to restore barrier
  16. 16Effective from as low as 3% with even more benefits for dry skin at higher concentrations up to 20-40%
  17. 17High-glycerin moisturizers are awesome for treating severely dry skin
  18. 18A form of skincare superstar, vitamin C. If you do not know why vitamin C is such a big deal in skincare, we have a really detailed, geeky description that's good to read. :)
  19. 19So now you know that because pure vitamin C is such a diva (very unstable and hard to formulate) the cosmetic industry is trying to come up with some derivatives that have the badass anti-aging properties of vitamin C (antioxidant protection + colla…
  20. 20First, it's really stable and easy to formulate, so the problems that come with pure vitamin C are solved here.
Source · incidecoder.com
02

Product index

Related product references

Product

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Paula's Choice Earth Sourced Toner Paula's Choice Earth Sourced Toner ingredients explained: Aqua, Glycerin (Hydration/Skin Replenishing), Leuconostoc/Radish Root Ferment Filtrate (Preserva…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side