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Skin science article

First Aid Beauty KP Bump Eraser Body Scrub With 10% AHA Versus Naturium KP Body Scrub & Mask

First Aid Beauty KP Bump Eraser Body Scrub With 10% AHA Versus Naturium KP Body Scrub & Mask This smoothing exfoliator is formulated around Glycolic Acid and Gluconolactone to refine skin texture and brighten dull-looking skin. What's inside Key Ingredients Be

First Aid Beauty KP Bump Eraser Body Scrub With 10% AHA Versus Naturium KP Body Scrub & Mask

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

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Pumice

Water

Glycolic Acid

Sodium Cocoyl Isethionate

Lactic Acid

Dimethicone

Stearic Acid

Cetearyl Alcohol

Sodium Hydroxide

Palmitic Acid

Glycerin

C12-15 Alkyl Benzoate

Sorbitol

Fragaria Chiloensis Fruit Extract

Colloidal Oatmeal

Tocopheryl Acetate

Bisabolol

Chrysanthemum Parthenium Extract

Glycyrrhiza Glabra Root Extract

Salix Nigra Bark Extract

Camellia Sinensis Leaf Extract

Phenoxyethanol

Isopropyl Myristate

Coconut Acid

Xanthan Gum

Steareth-20

Steareth-21

Sodium Isethionate

Butylene Glycol

Ethyl 2-Methylbutyrate

Ambroxide

Potassium Sorbate

Sodium Benzoate

Cis-3-Hexenyl Formate

Methyl Methylbutyrate

Tetrasodium EDTA

Leuconostoc/Radish Root Ferment Filtrate

Pumice, Water, Glycolic Acid, Sodium Cocoyl Isethionate, Lactic Acid, Dimethicone, Stearic Acid, Cetearyl Alcohol, Sodium Hydroxide, Palmitic Acid, Glycerin, C12-15 Alkyl Benzoate, Sorbitol, Fragaria Chiloensis Fruit Extract, Colloidal Oatmeal, Tocopheryl Acetate, Bisabolol, Chrysanthemum Parthenium Extract, Glycyrrhiza Glabra Root Extract, Salix Nigra Bark Extract, Camellia Sinensis Leaf Extract, Phenoxyethanol, Isopropyl Myristate, Coconut Acid, Xanthan Gum, Steareth-20, Steareth-21, Sodium Isethionate, Butylene Glycol, Ethyl 2-Methylbutyrate, Ambroxide, Potassium Sorbate, Sodium Benzoate, Cis-3-Hexenyl Formate, Methyl Methylbutyrate, Tetrasodium EDTA, Leuconostoc/Radish Root Ferment Filtrate

CI 77891

Jojoba Esters

Gluconolactone

Salicylic Acid

Simmondsia Chinensis Seed Oil

Squalane

Sodium Hyaluronate

Hippophae Rhamnoides Fruit/Seed Oil

Niacinamide

Rosa Canina Fruit Oil

Glycine Soja Oil

Ethylhexylglycerin

Tetrasodium Glutamate Diacetate

Tocopherol

Water, Pumice, Glycolic Acid, Stearic Acid, Cetearyl Alcohol, CI 77891, Sodium Hydroxide, Jojoba Esters, Gluconolactone, Glycerin, Sodium Cocoyl Isethionate, Dimethicone, Salicylic Acid, Simmondsia Chinensis Seed Oil, Squalane, Sodium Hyaluronate, Leuconostoc/Radish Root Ferment Filtrate, Bisabolol, C12-15 Alkyl Benzoate, Hippophae Rhamnoides Fruit/Seed Oil, Niacinamide, Rosa Canina Fruit Oil, Camellia Sinensis Leaf Extract, Glycyrrhiza Glabra Root Extract, Glycine Soja Oil, Steareth-20, Xanthan Gum, Steareth-21, Phenoxyethanol, Ethylhexylglycerin, Tetrasodium Glutamate Diacetate, Tocopherol

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.

Bisabolol is a gentle skin conditioner, antioxidant, and soothing ingredient.

It's primary claim to fame is soothing and research shows topically applied bisabolol can quiet the chemical messengers that cause your skin to become inflamed, helping to sooth any irritation.

A clinical study found that applying 0.5% bisabolol daily for 8 weeks produced an average 9% decrease in skin pigmentation. Researchers found it can also suppress the process that leads to excess melanin production in skin.

In vitro studies found that bisabolol combined with propylene glycol significantly increased skin permeability by increasing lipid fluidity in the stratum corneum.

You'll likely see use concentrations quite low, usually 0.1-0.2%.

Overall, this is a well-tolerated ingredient that works well in formulas designed for sensitive, reactive, or post-procedure skin.

C12-15 Alkyl Benzoate is a lightweight emollient made by combinig benzoic acid with fatty alcohols that are 12-15 carbons long.

In cosmetics, it plays several roles:

The Cosmetic Review Expert Panel has concluded the alkyl benzoate group to be safe as used in cosmetics; it wasn't found to be a skin irritant and unlikely to be absorbed due to its low water solubility.

This report recorded almost 1000 reported uses with concentrations up to 59% in leave-on products but your cosmetics will typically use 0.5-15% depending on the product.

It's often called a "SPF booster": this is because it keeps UV filters properly dissolved and evenly distributed to support a sunscreen's performance. It doesn't actually raise SPF on its own.

Overall, this ingredient is well tolerated.

This ingredient is fungal acne safe because it is an ester of benzoic acid.

Think of this ingredient as two parts stuck together: an oily part and an acid part. Malassezia only gets a meal when it can snip off a fatty acid to eat. With C12-15 Alkyl Benzoate, the acid part is benzoic acid, which isn't a fatty acid and which the yeast can't use as food.

Benzoic acid is actually used as a preservative to stop yeast from growing.

The oily part is a blend of C12-15 fatty alcohols but fatty alcohols in this size range can support only a little Malassezia growth (mostly for one species of Malassezia as well).

In the ingredient, those alcohols stay locked inside the molecule. The yeast can only reach them by snipping the benzoate bond, and that type of bond is harder for it to cut than a normal fatty bond.

So not much gets released. And whatever does get snipped comes packaged with benzoic acid, which discourages yeast growth.

Camellia Sinensis Leaf Extract (tea extract) is one of the most well-researched plant extracts in skincare with an impressive resume.

Black tea, green tea, and oolong tea are all harvested from the Camellia Sinensis plant.

Studies show green tea extract and its catechins (like epigallocatechin gallate (EGCG)) help your skin cells product energy more efficiently and reducing the number of free-radicals that can damage your skin from the inside.

In lab-grown skin models, this translated to younger, healthier, and stronger skin.

There's also good sun protection data; researchers saw less DNA damage and redness on human skin when green tea was applied before UVB exposure. And the more they applied, the better the protection.

Needless to say, this ingredient shouldn't replace your sunscreen. But it is a great supportive ingredient that you can already find in many sunscreens and antioxidant serums.

A 2009 study found a 2% green tea lotion was effective for mild-to-moderate acne thanks to its anti-inflammatory and mild antimicrobial activity.

The quality of the extract matters a lot here:

Good extracts contain 50-90% catechins while lower quality ones are mostly there for marketing. We recommend reaching out to the brand if you have questions about the quality or source of their ingredients.

Human Repeated Insult Patch Testing showed no irritation or sensitization at use concentrations (0.86% in leave-on products and up to 30% as leaf water).

Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.

Despite having "alcohol" in its name, it has nothing to do with drying solvent alcohols; the FDA also allows "alcohol-free" products to contain fatty alcohols like this ingredient.

It plays several roles in a formula:

Typical use levels for this ingredient sit around 1-10% and the Cosmetic Ingredient Review Expert Panel has affirmed safety at concentrations up to 25% in leave-on products.

Multiple assessments have found it to be non-irritating and non-sensitizing to most people.

However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.

Cetearyl alcohol has a comedogenic rating of 2 and irritancy rating of 1. Both of these numbers come from the 1989 study that used rabbit ears; a "2" means mildly comedogenic and a "1" means low irritancy.

Here's the catch: rabbit skin is more sensitive than human skin and throws a lot of false positives. A 1996 reappraisal found that ingredients rated 1-2 in the rabbit ear tests are generally safe for humans.

Remember comedogenic ratings are unable to assess the entire formula of a product or how it will react on your skin. Just be sure to patch test if you are unsure about certain ingredients.

This ingredient is not fungal acne safe. Cetearyl alcohol is a fatty alcohol with chain lengths that fall within the range that Malassezia can metabolize.

A 2019 study has also observed Malassezia growth in the presence of this ingredient, confirming it to be not-fungal acne safe.

Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.

What it does:

Dimethicone comes in different viscosities:

Depending on the viscosity, dimethicone has different properties.

Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.

This ingredient is unlikely to cause irritation because it does not get absorbed into skin. However, people with silicone allergies should be careful about using this ingredient.

Note: Dimethicone may contribute to pilling. This is because it is not oil or water soluble, so pilling may occur when layered with products. When mixed with heavy oils in a formula, the outcome is also quite greasy.

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.

Glycolic Acid is arguably the most famous alpha hydroxy acid (AHA) with tons of research backing its benefits.

It is found naturally in sugar cane but the form used in skincare is usually synthetic for purity and stability.

Glycolic acid removes the top layer of dead skin cells to allow newer and fresher ones to emerge.

AHAs work by breaking down the structural “glue” that holds old skin cells in place. When that buildup is gone, your skin can renew itself more efficiently.

Research also shows glycolic acid stimulates collagen production, helping to firm and thicken the skin over time. This is one of its biggest advantages over other AHAs.

Overall, glycolic acid helps with:

Fun fact: Glycolic acid boosts skin hydration by helping it produce molecules that increase hyaluronic acid naturally.

To work best, glycolic acid products should have a pH between 3-4 (that’s where exfoliation is most effective but still gentle on skin).

The pH and concentration of a product are key to its effectiveness:

It is normal to feel a slight stinging sensation when using glycolic acid. This usually fades as your skin adjusts.

Because glycolic acid has the smallest molecular size in the AHA family, it can penetrate deeper, which enhances its effectiveness but also makes it more likely to irritate sensitive skin.

If your skin is very sensitive or prone to rosacea, glycolic acid may be too strong; in that case, try milder options like lactic acid or a PHA instead.

Recent studies suggest glycolic acid might even help protect against UV damage. But don’t skip sunscreen! Freshly exfoliated skin is more sensitive to the sun.

Glycolic acid is a skincare superstar. It smooths, brightens, hydrates, and firms the skin. Unless you’re highly sensitive, it’s well worth adding to your routine.

Read more about some other popular AHA's here:

Glycyrrhiza Glabra Root Extract is an extract of the roots of Licorice. It has been found to have several benefits such as skin hydrating, conditioning, and soothing.

One component, glabridin, has extra potent antioxidant and soothing properties. It has also been found to block pigmentation from UVB rays in guinea pigs.

Licorice Root also contains a flavonoid. Flavonoids are a natural substance from in plants. Flavonoids also have antioxidant properties.

Another component, glycyrrhizin, has been found to have anti-inflammatory and antimicrobial benefits. This may make licorice root extract effective at treating acne. However, more research is needed to support this.

Liquiritin is one of the flavone compounds found in licorice. It has been found to help lighten skin by preventing tyrosinase from reacting with tyrosine. When the two react, protein is converted to melanin. Melanin is the substance in your body that gives your features pigmentation.

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).

Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).

It has a large spectrum of antimicrobial activity and especially effective bacteria, yeast, and mold while only having a weak effect on your skin's natural microbiome.

On a cellular level, it disrupts the cell membranes of microbes by poking holes that make the cell leak. This shuts down the chemical reactions the microbe needs to make energy so it can no longer survive.

Another perk of this ingredient is that it stays functional across a wide pH range (3-10).

You'll often see it paired with boosters like Ethylhexylglycerin; one study showed that a 1:9 ratio of Ethylhexylglycerin to Phenoxyethanol damages bacterial membranes as effectively as doubling the Phenoxyethanol concentration on its own.

Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.

Safety-wise, the fear mongering does not hold up to the evidence. The EU's Scientific Committee on Consumer Safety and FDA consider it safe as a preservative at up to 1%, including for children of all ages.

Adverse systemic effects only showed up in animal studies at exposures roughly 200x higher than what people get from cosmetics. And despite its very widespread use, this ingredient is a rare sensitizer and allergic reactions are uncommon.

Pumice is an exfoliant.

Sodium cocoyl isethionate is a natural ingredient from coconut oil. It is an ultra gentle cleanser that gives a nice foam without drying the skin or impacting the skin barrier.

The amount of foam created depends on the amount of sodium cocoyl isethionate used in the product.

This ingredient also helps improve the spreadability of a product.

This ingredient hasn’t been shown in studies to feed fungal acne yeast.

Sodium Hydroxide is also known as lye or caustic soda. It is used to adjust the pH of products; many ingredients require a specific pH to be effective.

In small amounts, sodium hydroxide is considered safe to use. However, large amounts may cause chemical burns due to its high alkaline.

Your skin has a natural pH and acid mantle. This acid mantle helps prevent harmful bacteria from breaking through. The acid mantle also helps keep your skin hydrated.

"Alkaline" refers to a high pH level. A low pH level would be considered acidic.

Steareth-20 is an emulsifier and solubilizer. It is created from stearyl alcohol with ~20 units of ethylene oxide to give it a strong preference for water.

As an emulsifier, it helps oil-in-water emulsions like lotions, creams, and cleansers stay stable. It also solubilizes small amounts of oil-loving ingredients (like fragrance) into water-based formulas.

You'll likely find this ingredient with steareth-2 (it's oil-loving sister) where the two work together to give products a cushiony feel.

Typical use levels sit at around 1-5% and this ingredient has been found to be non-irritating by the CIR Expert Panel.

Steareth-21 is a nonionic emulsifier made by reacting stearyl alcohol with 21 units of ethylene oxide. It is mainly a cleansing agent and emulsifier.

The "21" in the name just tells you it has a longer water-loving chain. This makes it more gentle and less likely to irritate skin compared to lower-numbered steareths.

You'll most likely see it paired with steareth-2 because the two work together to create stable formulations.

1,4-dioxane is often brought up as a concern but this is usually removed through purification.

Stearic Acid is a fatty acid that is already found in your skin. It's one of the free fatty acids that works alongside ceramides and cholesterols to maintain your barrier.

In cosmetics, it is a multitasker:

Safety-wise, the CIR Expert Panel has concluded it to be safe in cosmetics when formulated to be non-irritating and non-sensitizing.

Free stearic acid is a C18 fatty acid that the Malassezia yeast can substrate, so this ingredient may not be fungal acne safe.

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

First Aid Beauty Ultra Repair Wild Oat Hydrating TonerIngredients 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. 06A natural moisturizer that’s also in our skin
  7. 07A super common, safe, effective and cheap molecule used for more than 50 years
  8. 08Not 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
  9. 09Effective from as low as 3% with even more benefits for dry skin at higher concentrations up to 20-40%
  10. 10High-glycerin moisturizers are awesome for treating severely dry skin
  11. 11It's a nice glycerin-based humectant and emollient that gives skin a smooth and luxurious feel.
  12. 12It seems to us that squalane is in fashion and there is a reason for it. Chemically speaking, it is a saturated (no double bonds) hydrocarbon (a molecule consisting only of carbon and hydrogen), meaning that it's a nice and stable oily liquid with a…
  13. 13It occurs naturally in certain fish and plant oils (e.g. olive), and in the sebum (the oily stuff our skin produces) of the human skin. As f.c. puts it in his awesome blog post, squalane's main things are "emolliency, surface occlusion, and TEWL pre…
  14. 14Another advantage of squalane is that it is pretty much compatible with all skin types and skin conditions. It is excellent for acne-prone skin and safe to use even if you have fungi-related skin issues, like seborrhea or fungal acne.
  15. 15The unsaturated (with double bonds) and hence less stable version of Squalane is Squalene, you can read about it here >>
  16. 16A mainly oil-loving, vegetable raw material based ingredient that helps water and oil to mix together, aka emulsifier. It can also function as a wetting and dispersing agent helping insoluble particles such as color pigments or inorganic sunscreens …
  17. 17Chemically speaking, it comes from the attachment of sorbitan (a dehydrated sorbitol (sugar) molecule) with the unsaturated fatty acid Oleic Acid, that creates a partly water (the sorbitan part) and partly oil soluble (oleic part) molecule.
  18. 18We don't have description for this ingredient yet.
  19. 19We all know honey as the sweet, gooey stuff that is lovely to sweeten a good cup of tea and we have good news about putting honey all over our skin. It is just as lovely on the skin as it is in the tea.
  20. 20The great review article about honey in the Journal of Cosmetic Dermatology writes that it is arguably the oldest skincare ingredient and evidence from around 4500 BC mentions honey in some eye cream recipes. Chemically speaking, it is a bee-derived…
Source · incidecoder.com
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Product index

Related product references

03

Comparison edit

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