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Necessaire The Body Retinol Versus First Aid Beauty KP Smoothing Body Lotion

Necessaire The Body Retinol Versus First Aid Beauty KP Smoothing Body Lotion What's inside Key Ingredients Benefits Concerns Ingredients Side-by-side Water Glycolic Acid Mandelic Acid Rosa Damascena Flower Water Caprylic/Capric Triglyceride Glycerin Cetearyl A

Necessaire The Body Retinol Versus First Aid Beauty KP Smoothing Body Lotion

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycolic Acid

Mandelic Acid

Rosa Damascena Flower Water

Caprylic/Capric Triglyceride

Glycerin

Cetearyl Alcohol

Sodium Hydroxide

Coconut Alkanes

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

1,2-Hexanediol

Cetearyl Olivate

Sorbitan Olivate

Propanediol

Silica

Silica Silylate

Magnesium Stearate

Niacinamide

Retinol

Sh-Oligopeptide-1

Sh-Oligopeptide-2

Sh-Polypeptide-1

Sh-Polypeptide-9

Sh-Polypeptide-11

Tocopherol

Tetrahexyldecyl Ascorbate

Bacillus/Folic Acid Ferment Filtrate Extract

Cellulose Acetate Butyrate

C13-14 Alkane

C15-23 Alkane

Tricaprylin

Acetyl Glutamine

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate

Lecithin

Citric Acid

Hippophae Rhamnoides Fruit Oil

Coco-Caprylate/Caprate

Decyl Glucoside

Sodium Hyaluronate

Caprylyl Glycol

Sodium Benzoate

Potassium Sorbate

Sodium Carbonate

Sodium Chloride

Ethylhexylglycerin

Hydroxyacetophenone

Citronellol

Geraniol

Water, Glycolic Acid, Mandelic Acid, Rosa Damascena Flower Water, Caprylic/Capric Triglyceride, Glycerin, Cetearyl Alcohol, Sodium Hydroxide, Coconut Alkanes, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, 1,2-Hexanediol, Cetearyl Olivate, Sorbitan Olivate, Propanediol, Silica, Silica Silylate, Magnesium Stearate, Niacinamide, Retinol, Sh-Oligopeptide-1, Sh-Oligopeptide-2, Sh-Polypeptide-1, Sh-Polypeptide-9, Sh-Polypeptide-11, Tocopherol, Tetrahexyldecyl Ascorbate, Bacillus/Folic Acid Ferment Filtrate Extract, Cellulose Acetate Butyrate, C13-14 Alkane, C15-23 Alkane, Tricaprylin, Acetyl Glutamine, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate, Lecithin, Citric Acid, Hippophae Rhamnoides Fruit Oil, Coco-Caprylate/Caprate, Decyl Glucoside, Sodium Hyaluronate, Caprylyl Glycol, Sodium Benzoate, Potassium Sorbate, Sodium Carbonate, Sodium Chloride, Ethylhexylglycerin, Hydroxyacetophenone, Citronellol, Geraniol

Lactic Acid

C12-15 Alkyl Benzoate

Palmitic Acid

Dimethicone

Stearic Acid

Glyceryl Stearate

Glyceryl Stearate Se

Urea

Allantoin

Colloidal Oatmeal

Ceramide NP

Camellia Sinensis Leaf Extract

Glycyrrhiza Glabra Root Extract

Chrysanthemum Parthenium Extract

Sodium Phytate

Sodium PCA

Xanthan Gum

Phenoxyethanol

Tetrasodium EDTA

Water, Lactic Acid, Propanediol, C12-15 Alkyl Benzoate, Caprylic/Capric Triglyceride, Silica, Sodium Hydroxide, Palmitic Acid, Dimethicone, Stearic Acid, Glyceryl Stearate, Glyceryl Stearate Se, Glycerin, Urea, Allantoin, Colloidal Oatmeal, Ceramide NP, Camellia Sinensis Leaf Extract, Glycyrrhiza Glabra Root Extract, Chrysanthemum Parthenium Extract, Sodium Phytate, Sodium PCA, Xanthan Gum, Cetearyl Alcohol, Phenoxyethanol, Potassium Sorbate, Sodium Benzoate, Tetrasodium 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.

Caprylic/Capric Triglyceride (aka MCT Oil) is a lightweight emollient, solvent, and texture enhancer. It is considered a skin-softener by helping to prevent moisture loss.

Though it behaves like an oil, it is not technically one due to its chemical composition. One perk of this ingredient is that it is very stable, resistant to oxidation, and unlikely to go rancid.

In practice, that translates to a long shelf life and a consistently elegant skin feel.

While there is an assumption Caprylic Triglyceride can clog pores due to it being derived from coconut oil, there is no research supporting this. Just patch test if you have concerns.

Fractionated coconut oil and MCT Oil are both listed as Caprylic/Capric Triglyceride according to INCI. This is because INCI names are based on the ingredient’s final chemical composition and not its marketing name or source.

This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.

This leaves just caprylic (C8) and capric (C10) acid. These chain lengths actually trend antifungal; a 2020 study found caprylic acid was enough to disrupt Malassezia furfur cell membrane, with a caprylic acid derivative damaging membrane structures at concentrations as low as 0.2%.

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.

Potassium Sorbate is a preservative used to prevent yeast and mold in products. It is commonly found in both cosmetic and food products.

This ingredient comes from potassium salt derived from sorbic acid. Sorbic acid is a natural antibiotic and effective against fungus.

Both potassium sorbate and sorbic acid can be found in baked goods, cheeses, dried meats, dried fruit, ice cream, pickles, wine, yogurt, and more.

You'll often find this ingredient used with other preservatives.

Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin.

It’s often used to:

Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.

Silica, also known as silicon dioxide, is a naturally occurring mineral. It is used as a fine, spherical, and porous powder in cosmetics.

Though it has exfoliant properties, the function of silica varies depending on the product.

The unique structure of silica enhances the spreadability and adds smoothness, making it a great texture enhancer.

It is also used as an active carrier, emulsifier, and mattifier due to its ability to absorb excess oil.

In some products, tiny microneedles called spicules are made from silica or hydrolyzed sponge. When you rub them in, they lightly polish away dead skin layers and enhance the penetration of active ingredients.

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.

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.

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.

01

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. 03Caffeine is a naturally occurring plant compound found in coffee beans, tea leaves, cocoa pods, and guarana.
  4. 04As an antioxidant, caffeine protects your skin from free radical damage caused by UV exposure and envionrmnetal stressors.
  5. 05Early research also shows that caffeine can help calm redness, soothe irritated skin, and support hair growth by stimulating microcirculation in the scalp.
  6. 06You might have seen eye creams marketing caffeine as a depuffing ingredient. This is because it is a vasoconstrictor meaning it can temporarily constrict blood vessels, though clinical evidence for this specific use is still limited.
  7. 07Most skincare products contain this ingredient at concentrations between 1-6%. It is able to penetrate skin easily regardless of skin type or thickness.
  8. 08Just so you know, a very small number of case reports describe caffeine-induced allergy. This ingredient is generally well-tolerated, non-irritating, and non-sensitizing for the majority of people.
  9. 09Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.
  10. 10Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.
  11. 11Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).
  12. 12Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.
  13. 13Like 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.
  14. 14However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.
  15. 15Due 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.
  16. 16In skincare formulas, citric acid can:
  17. 17While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.
  18. 18Most 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.
  19. 19Rosacea 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.
  20. 20However, 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…
Source · skinsort.com
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Product index

Related product references

03

Comparison edit

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