Q + A Zinc PCA Facial Serum

Q + A Zinc PCA Facial Serum

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Overview

What it is

Serum with 19 ingredients that contains zinc

Cool Features

It is vegan, cruelty-free, and reef safe

Suited For

It has ingredients that are good for fighting acne, anti aging, dry skin, sensitive skin, oily skin, reducing pores and scar healing

Free From

It doesn't contain any harsh alcohols, common allergens, fragrances, oils, parabens, silicones or sulfates

Fun facts

Q + A is from United Kingdom. This product is used in 83 routines created by our community.

We independently verify ingredients and our claims are backed by peer-reviewed research. Does this product need an update? Let us know.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Explained

Skin Conditioning, Solvent

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!

Learn more about Water
Humectant, Skin Conditioning, Solvent

Propylene Glycol is a synthetic, colorless, odorless liquid that has been a staple in cosmetics for decades. It is a skin conditioning agent, humectant, and solvent.

As a humectant, it draw water to the skin to reduce flaking and restore suppleness. It's also a solvent that helps dissolve other actives and keeps formulas stable across temperature changes.

The CIR Expert Panel has confirmed this ingredient to be nontoxic and clinical studies show no sensitization at cosmetic use concentrations.

True allergic reactions are quite rare: a 15-year retrospective study of 6,751 patients found only 0.31% had a positive reaction (and less than half were considered clinically relevant).

It seemed that when sensitization does occur, it's most commonly linked to topical medication (like corticosteroids) and not cosmetics. Allergic contact dermatitis also appears largely limited to individuals with underlying skin conditions.

Overall, propylene glycol is a well-studied ingredient that most people can tolerate without issue.

Learn more about Propylene Glycol

We don't have a description for Lactobacillus/Ganoderma Lucidum Extract/Lentinus Edodes Extract Ferment Filtrate yet.

Humectant, Skin Conditioning

Betaine is a humectant. Like hyaluronic acid, it helps attract and retain moisture in the skin. Itโ€™s known for being gentle and for helping the skin maintain balanced hydration.

Betaine is mainly used to improve hydration and support calmer skin. It helps skin cells regulate water balance because it functions as an osmolyte.

Some studies suggest betaine may support making skin tone more even.

Fun fact: Betaine naturally exists in the skin and the body. In cosmetic products, it can be either plant-derived (most commonly from sugar beets) or synthetically produced for consistency and stability.

Betaine is also known as trimethylglycine.

Learn more about Betaine
Skin Conditioning, Solvent

Pentylene glycol is typically used within a product to thicken it. It also adds a smooth, soft, and moisturizing feel to the product. It is naturally found in plants such as sugar beets.

The hydrophilic trait of Pentylene Glycol makes it a humectant. As a humectant, Pentylene Glycol helps draw moisture from the air to your skin. This can help keep your skin hydrated.

This property also makes Pentylene Glycol a great texture enhancer. It can also help thicken or stabilize a product.

Pentylene Glycol also acts as a mild preservative and helps to keep a product microbe-free.

Some people may experience mild eye and skin irritation from Pentylene Glycol. We always recommend speaking with a professional about using this ingredient in your routine.

Pentylene Glycol has a low molecular weight and is part of the 1,2-glycol family.

Learn more about Pentylene Glycol
Humectant, Skin Conditioning

Zinc PCA (or "zinc salt") differs slightly from zinc itself. PCA stands for pyrrolidone carboxylic acid. However, Zinc PCA comes from zinc.

It can help reduce redness, regulate sebum, and promote the general healing process of the skin.

Zinc PCA tends to be especially useful for those with oily, acne-prone skin. It's certainly an ingredient worth trying out!

Learn more about Zinc PCA
Skin Conditioning

This ingredient is made when the Lactobacillus bacteria (the same kind that makes yogurt and kimchi) are allowed to ferment a nutrient medium.

As it ferments, it collects lactic acid, peptides, enzymes, and other bioactive metabolites to provide:

A 2023 review noted that probiotic fermentation ingredients like this one can enhance antioxidant capacity, reduce UV-induced oxidative damage, and support barrier function.

One clinical study from the same year showed a Lactobacillus ferment lysate significantly reduced transepidermal water loss and improved skin hydration.

Another review highlighted that topical Lactobacillus-based preparations can improve ceramide levels in the stratum corneum, support barrier integrity, and even help reduce S. aureus colonization in atopic dermatitis.

Why is this so cool?

Basically, your skin's outer layer works as a brick wall; skin cells are bricks and ceramides are the mortar holding it together. Moisture escapes, irritants get in, and your skin gets dry and reactive when ceramide levels drop. On top of that, "bad" skin bacteria S. aureus loves to move in when your barrier is weak to make inflammation and irritation worse.

So Lactobacillus ferment is basically patching the wall and evicting the troublemaker when it boosts ceramide production and help keep S. aureus in check.

On top of all this, it also acts as a mild antimicrobial preservative booster.

Just so you know, most studies focus on specific strains or the lysate form rather than this generic "Lactobacillus Ferment", so results can vary.

Though it's a promising ingredient, it doesn't have decades of robust clinical data behind it just yet.

Lactobacillus Ferment is generally considered safe for fungal-acne prone skin. The key thing to understand is that it comes from bacteria, not yeast or fungus.

Yeast-derived ferments (like galactomyces) have been shown to activate a protein that's linked to Malassezia-related skin issues whereas lactobacillus doesn't have that problem.

Its byproducts also don't contain the types of fatty acids (C11-24 chain lengths) that Malassezia feeds on.

Learn more about Lactobacillus Ferment
Astringent, Masking

This ingredient is derived from parts of the Italian honeysuckle plant. It has astringent, antioxidant, and antimicrobial properties.

Honeysuckle has a natural fragrance.

Lonicera Japonica Flower Extract comes from the honeysuckle flower.

Honeysuckles have skin protecting, anti-viral, and anti-inflammatory properties. It contains many antioxidants, such as luteolin, caffeic acid, loniflavone, and chlorogenic acids.

This honeysuckle is native to East Asia and used in traditional Chinese medicine to treat fever and inflammation.

Learn more about Lonicera Japonica Flower Extract
Buffering, Humectant, Skin Conditioning

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 โ€œglueโ€ 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 donโ€™t penetrate as deeply. This means theyโ€™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 skinโ€™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 productโ€™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:

Learn more about Lactic Acid
Emollient, Emulsifying

Glyceryl Caprylate comes from glycerin and caprylic acid. It is an emollient, co-emulsifier, and preservative booster.

Its short C8 fatty acid chain makes it behave differently from its longer-chain emollient cousins like Glyceryl Stearate. It feels more lightweight, fast-absorbing, and silky instead of rich and waxy.

As a co-emulsifier, its "head" and "tail" sit at the oil-water interface. But overall, the short C8 tail and not being water soluble means it doesn't really have the muscle to emulsify a formula on its own. That's why you'll often see it paired with a primary emulsifier like Cetearyl Glucoside.

Interestingly, Glyceryl Caprylate acts as a preservative booster. This is because its fatty-acid backbone disrupts microbial lipid membranes. It shows excellent activity against bacteria and yeast but is weaker against mold.

Typical concentrations range from 0.5-1% and this ingredient is generally non-irritating.

Because this ingredient has a C8 fatty acid chain, it is outside the range that the Malassezia yeast metabolizes (making it fungal acne safe).

Learn more about Glyceryl Caprylate
Humectant, Skin Conditioning

Biosaccharide Gum-1 is a sugar created by fermenting sorbitol (which usually comes from potato starch!). It is known for its soothing and moisturizing properties.

Manufacturer tests show this ingredient helped reduce irritation from lactic acid by almost half and kept skin hydrated long-term as a humectant

Beyond hydration, Biosaccharide Gum-1 gives formulas a silky, non-sticky feel.

This ingredient is gentle, versatile, and suitable for all skin types.

Fun fact: Similar sugars can be found naturally in fruits like apples and pears.

Learn more about Biosaccharide Gum-1
Moisturising, Skin Conditioning

Collagen is a big structural protein that your body uses to keep skin firm and bouncy. Despite the marketing, topically applied collagen doesn't "refill" the collagen in your skin.

The molecule is too big to pass through your skin barrier so intact Collagen physically can't get past the surface.

What it actually does in your skincare is work as a humectant and film-former: it binds water, lays down a light moisturizing film, and reduces water loss from the surface. This helps make skin feel smoother and temporarily plumper.

This ingredient has been found safe for use in cosmetics with clinical studies showing no irritation, sensitization, or phototoxicity. It's typically used at low concentrations (often a fraction of a percent up to a few percent).

Collagen will not increase sun sensitivity, but you should always wear sunscreen during the day.

Learn more about hydrolyzed collagen or soluble collagen.

Learn more about Collagen
Humectant, Skin Conditioning, Skin Protecting

Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.

Topically, glycerin does several things at once:

Your 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.

Aquaporin-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.

This 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.

Just know very high concentrations (>40%) can feel tacky in low humidity.

Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.

Learn more about Glycerin

Leuconostoc/Radish Root Ferment Filtrate is a natural preservative. It comes from fermenting radish roots with a bacteria called leuconostoc. The trade name for this ingredient is Leucidal.

Leuconostoc comes from lactic acid.

This ingredient has antimicrobial properties and helps prevent the growth of bacteria in a product.

Leuconostoc is used to make the traditional Korean side-dish, kimchi. It is also used to make sourdough bread (both incredibly yummy foods).

Learn more about Leuconostoc/Radish Root Ferment Filtrate
Skin Conditioning

Sodium levulinate is the a sodium salt of Levulinic Acid. Oncedissolved in an aqueous solution, the two ingredients become identical. It is usually derived from renewable plant sources like corn starch or sugarcane.

In skincare, it mostly acts as a skin conditioning agent that keeps skin soft and hydrated. It also acts as a preservative booster by inhibiting the growth of mold, yeast, and bacteria.

It's often paired with Sodium Anisate as the two create a broad-spectrum preservative system that is popular in "natural" formulations.

This ingredient is water-soluble.

The CIR Expert Panel for Cosmetic Ingredient Safety has concluded this ingredient to be non-irritated and there are no restrictions for use in EU cosmetics. The FDA also allows this ingredient to be used as a food-grade flavoring agent.

Learn more about Sodium Levulinate
Antimicrobial

Sodium Anisate comes from fennel. It is used as a preservative and to add flavoring.

Sodium Anisate has antimicrobial properties.

Skin Conditioning

This is the synthetic salt of gluconic acid, a form of PHA and mild exfoliant.

It is mainly used to stabilize oil and butter formulations from going bad. Sodium gluconate is a humectant, pH regulator, and chelating agent.

Chelating agents help neutralize unwanted metals from affecting the formulation.

Sodium gluconate is water-soluble.

Learn more about Sodium Gluconate
Emulsifying, Emulsion Stabilising, Gel Forming

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.

Learn more about Xanthan Gum

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Absorbs Well 75% Light 75% Works Well 75%
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Where it's from

Q + A is a British brand

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ยท Updated May 30, 2026 Added by Dewy27