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First Aid Beauty KP Bump Eraser Body Scrub With 10% AHA Versus Amlactin KP Bumps Be Gone Cream With 15% Lactic Acid

First Aid Beauty KP Bump Eraser Body Scrub With 10% AHA Versus Amlactin KP Bumps Be Gone Cream With 15% Lactic Acid What's inside Key Ingredients Benefits Concerns Ingredients Side-by-side Pumice Water Glycolic Acid Sodium Cocoyl Isethionate Lactic Acid Dimeth

First Aid Beauty KP Bump Eraser Body Scrub With 10% AHA Versus Amlactin KP Bumps Be Gone Cream With 15% Lactic Acid

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

Colloidal Oatmeal

Tocopherol

Chrysanthemum Parthenium Extract

Camellia Sinensis Leaf Extract

Glycyrrhiza Glabra Root Extract

Salix Nigra Bark Extract

Bisabolol

Hydrogenated Coconut Acid

Xanthan Gum

Steareth-20

Steareth-21

Myristic Acid

Sodium Isethionate

Phenoxyethanol

Potassium Sorbate

Sodium Benzoate

Leuconostoc/Radish Root Ferment Filtrate

EDTA

Pumice, Water, Glycolic Acid, Sodium Cocoyl Isethionate, Lactic Acid, Dimethicone, Stearic Acid, Cetearyl Alcohol, Sodium Hydroxide, Palmitic Acid, Glycerin, C12-15 Alkyl Benzoate, Sorbitol, Colloidal Oatmeal, Tocopherol, Chrysanthemum Parthenium Extract, Camellia Sinensis Leaf Extract, Glycyrrhiza Glabra Root Extract, Salix Nigra Bark Extract, Bisabolol, Hydrogenated Coconut Acid, Xanthan Gum, Steareth-20, Steareth-21, Myristic Acid, Sodium Isethionate, Phenoxyethanol, Potassium Sorbate, Sodium Benzoate, Leuconostoc/Radish Root Ferment Filtrate, EDTA

Ammonium Lactate

Propylene Glycol

Paraffinum Liquidum

Petrolatum

Polysorbate 60

Steareth-2

Disodium EDTA

Water, Ammonium Lactate, Glycerin, Propylene Glycol, Paraffinum Liquidum, Petrolatum, Cetearyl Alcohol, Stearic Acid, Polysorbate 60, Steareth-21, Steareth-2, Xanthan Gum, Sodium Benzoate, Disodium EDTA

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.

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.

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.

Sodium Benzoate is a preservative. It's used in both cosmetic and food products to inhibit the growth of mold and bacteria. It is typically produced synthetically.

Both the US FDA and EU Health Committee have approved the use of sodium benzoate. In the US, levels of 0.1% (of the total product) are allowed.

Sodium benzoate works as a preservative by inhibiting the growth of bacteria inside of cells. It prevents the cell from fermenting a type of sugar using an enzyme called phosphofructokinase.

It is the salt of benzoic acid. Foods containing sodium benzoate include soda, salad dressings, condiments, fruit juices, wines, and snack foods.

Studies for using ascorbic acid and sodium benzoate in cosmetics are lacking, especially in skincare routines with multiple steps.

We always recommend speaking with a professional, such as a dermatologist, if you have any concerns.

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.

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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. 03Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  4. 04Topically, glycerin does several things at once:
  5. 05Your 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.
  6. 06Aquaporin-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.
  7. 07This 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.
  8. 08Just know very high concentrations (>40%) can feel tacky in low humidity.
  9. 09Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  10. 10Hydroxyacetophenone is a small phenolic molecule that earns its place in a formulas as an antioxidant and preservative booster.
  11. 11As a phenol, it is able to neutralize free radicals to protect both the product and the skin from oxidative stress.
  12. 12Though it can't kill microbes on its own, it works as a good supporting agent when combined with other preservatives like Phenoxyethanol or 1,2-Hexanediol.
  13. 13This ingredient naturally occurs as piceol in Norwegian spruce needles (~0.4-1.1% dry weight and in cloudberries). Though the cosmetic-grade material is synthesized for purity and consistency.
  14. 14You'll usually see it used at low levels and suppliers recommend up to 1% added to a water phase.
  15. 15Safety testing was done at concentrations like 0.05% in SPF products and 0.5% in a Human Repeated Insult Patch Test. The safety evidence is assuring; this ingredient is safe for cosmetics in current use and also holds safety status as a food flavori…
  16. 16An honest caveat: the "soothing" and "anti-inflammatory" claims come mostly from supplier marketing rather than published clinical trials. The Cosmetic Ingredient Review's own literature search found no useful efficacy studies on this ingredient.
  17. 17So the antioxidant and preservative-boosting roles are the well supported ones while the calming benefit is plausible but thinly evidenced.
  18. 18Overall, this is a well-tolerated, low-irritation multitasker that quietly helps a formula stay fresh and stable.
  19. 19Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).
  20. 20It 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.
Source · skinsort.com
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Product index

Related product references

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Comparison edit

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