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Paula's Choice C15 Super Booster - US Versus SkinBetter Science Alto Defense Serum

Facial Treatment
Serum
American Brand United States
American Brand United States

Updated on November 03, 2023

Overview

What they are

These products are both reef safe . They have a total of 10 ingredients in common

Cool Features

They both contain peptides, Vitamin C and Vitamin E

Suited For

They're both likely to be good for anti aging, dry skin, brightening skin, sensitive skin, scar healing, dark spots and better texture

Free From

They both do not contain any harsh alcohols, common allergens, parabens, silicones or sulfates

What's Inside

They both contain fragrances

We independently verify ingredients, and our claims are backed by peer-reviewed research. Spot a product that needs an update? Let us know.

Ingredient Info

Click any item below to learn more and see relevant ingredients

At a glance

Click on any of the items below to learn more

Notable Ingredients

Benefits

Concerns

Notable Ingredients

Benefits

Concerns

Ingredients Side-by-side

found in both products
C15 Super Booster
Water 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.

Ascorbic Acid Antioxidant, Buffering, Masking
Vitamin C IconAntioxidant IconHelps reduce Skin Redness IconGood for Skin Texture IconHelps with Anti-Aging IconGood for Dark Spots IconGood for Scar Healing IconHelps brighten skin Icon
Vitamin CVitamin C Icon AntioxidantAntioxidant Icon 6 Benefits

Ascorbic Acid is is pure Vitamin C. This form makes up the largest amount of vitamin C found naturally in our skin.

Butylene Glycol Humectant, Masking, Skin Conditioning
1 / 0

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

1 Com. / 0 Irr.
Ethoxydiglycol Humectant, Solvent
0 / 0

Ethoxydiglycol is a synthetic solvent.

0 Com. / 0 Irr.
Glycerin Humectant, Skin Conditioning, Skin Protecting
0 / 0 Helps hydrate Dry Skin IconHelps brighten skin Icon
2 Benefits

Glycerin is already naturally found in your skin. It helps moisturize and protect your skin.

0 Com. / 0 Irr.
Ppg-26-Buteth-26 Skin Conditioning

We don't have a description for Ppg-26-Buteth-26.

Disliked Full details ->
Peg-40 Hydrogenated Castor Oil Emulsifying
Oil IconNot safe for Fungal Acne Icon
OilOil Icon Not safe for Fungal AcneNot safe for Fungal Acne Icon

Peg-40 Hydrogenated Castor Oil is derived from castor oil and polyethylene glycol (PEG). It is used as a emollient and emulsifier.

Very Disliked Full details ->
Pentylene Glycol 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.

Tocopherol Antioxidant, Masking, Skin Conditioning
0-3 / 0-3 Vitamin E IconAntioxidant IconHelps hydrate Dry Skin IconHelps with Anti-Aging IconGood for Scar Healing IconHelps brighten skin IconMay cause irritation Icon
Vitamin EVitamin E Icon AntioxidantAntioxidant Icon 4 Benefits May cause irritationMay cause irritation Icon

Tocopherol (also known as Vitamin E) is a common antioxidant used to help protect the skin from free-radicals and strengthen the skin barrier. It's also fat soluble - this means our skin is great at absorbing it.

0-3 Com. / 0-3 Irr.
Sodium Hyaluronate Humectant, Skin Conditioning
0 / 0 Hyaluronic Acid Icon
Hyaluronic AcidHyaluronic Acid Icon

Sodium Hyaluronate is hyaluronic acid's salt form. It is commonly derived from the sodium salt of hyaluronic acid.

0 Com. / 0 Irr.
Hexanoyl Dipeptide-3 Norleucine Acetate Skin Conditioning
Peptide Icon
PeptidePeptide Icon

Hexanoyl Dipeptide-3 Norleucine Acetate is a peptide.

Lecithin Emollient, Emulsifying, Skin Conditioning

Lecithin is a term for a group of substances found in plants, animals, and humans. They are made up of mixture of fatty acids. These fatty acids usually are a mixture of phosphoric acid's choline ester connected to stearic, oleic, and palmitic acids. Most lecithins are created from plant ingredients scuh as sunflower.

Disliked Full details ->
Ferulic Acid Antimicrobial, Antioxidant
Antioxidant IconHelps with Anti-Aging Icon
AntioxidantAntioxidant Icon Helps with Anti-AgingHelps with Anti-Aging Icon

Ferulic Acid is a plant based antioxidant. Antioxidants help fight free-radicals. Free-radicals are molecules that may damage your skin cells. Ferulic Acid can help reduce the formation of fine lines and hyperpigmentation.

Panthenol Skin Conditioning
0 / 0 Helps reduce irritation Icon
Helps reduce irritationHelps reduce irritation Icon

Panthenol is a common ingredient that helps hydrate and soothe the skin. It can be found naturally in our skin and hair.

0 Com. / 0 Irr.
Bisabolol Masking, Skin Conditioning, Soothing
Helps reduce irritation Icon
Helps reduce irritationHelps reduce irritation Icon

Bisabolol is pimarily used to add fragrance to a product. However, it is also famous for helping soothe skin.

Oryza Sativa Bran Extract Skin Conditioning, Skin Protecting

Oryza Sativa Bran Extract comes from the outer layer of a rice kernel. It is a byproduct of milling rice, or the operation to produce a whole grain rice product.

Propyl Gallate Antioxidant, Perfuming
Antioxidant IconFragrance Icon
AntioxidantAntioxidant Icon FragranceFragrance Icon

Propyl Gallate is an antioxidant and is a fragrance.

Sodium Gluconate Skin Conditioning

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

Unknown Full details ->
Sodium Hydroxide Buffering

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.

Phenoxyethanol Preservative
Preservative Icon
PreservativePreservative Icon

Phenoxyethanol is a preservative that has germicide, antimicrobial, and aromatic properties. Studies show that phenoxyethanol can prevent microbial growth. By itself, it has a scent that is similar to that of a rose.

Very Disliked Full details ->
Ethylhexylglycerin Skin Conditioning

Ethylhexylglycerin (we can't pronounce this either) is commonly used as a preservative and skin softener. It is derived from glyceryl.

Alto Defense Serum
Water 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.

Butylene Glycol Humectant, Masking, Skin Conditioning
1 / 0

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

1 Com. / 0 Irr.
Propanediol Solvent

Propanediol helps absorb ingredients into your skin, boosting their benefits. It can act as an emollient, making your skin softer. Propanediol can help products last longer by boosting the properties of preservatives within the formulation.

Ethylhexyl Olivate Skin Conditioning
Not safe for Fungal Acne Icon
Not safe for Fungal AcneNot safe for Fungal Acne Icon

Ethylhexyl Olivate isn't fungal acne safe.

Very Disliked Full details ->
Cetearyl Alcohol Emollient, Emulsifying, Emulsion Stabilising
2 / 1 Fatty Alcohol IconMay worsen Oily Skin IconBad for Acne Prone Skin IconNot safe for Fungal Acne Icon
Fatty AlcoholFatty Alcohol Icon 3 Concerns

Cetearyl alcohol is a mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is mainly used as an emulsifier. Emulsifiers help prevent the separation of oils and products. Due to its composition, it can also be used to thicken a product or help create foam.

2 Com. / 1 Irr.
Very Disliked Full details ->
Chlorogenic Acids Antioxidant, Skin Conditioning, Skin Protecting
Antioxidant Icon
AntioxidantAntioxidant Icon

Chlorogenic acid refers to a group of related acids including caffeic acid, ferulic acid and p-coumaric acid.

Unknown Full details ->
Hydrolyzed Sodium Hyaluronate Skin Conditioning

This ingredient is created by putting sodium hyaluronate through hydrolysis.

Lauryl Lactate Emollient, Skin Conditioning

We don't have a description for Lauryl Lactate.

Unknown Full details ->
Dimethyl Isosorbide Solvent

Dimethyl Isosorbide is a solvent and helps deliver actives into your skin. It is created from sorbitol.

Glycyrrhiza Glabra Root Extract Bleaching, Emollient, Skin Conditioning
Good for Dark Spots Icon
Good for Dark SpotsGood for Dark Spots Icon

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.

Ascorbyl Tetraisopalmitate Antioxidant, Emollient, Skin Conditioning
Vitamin C IconAntioxidant IconHelps reduce Skin Redness IconGood for Skin Texture IconHelps with Anti-Aging IconGood for Dark Spots IconNot safe for Fungal Acne Icon
Vitamin CVitamin C Icon AntioxidantAntioxidant Icon 4 Benefits Not safe for Fungal AcneNot safe for Fungal Acne Icon

Ascorbyl Tetraisopalmitate is a version of ascorbic acid, or pure Vitamin C.

Ergothioneine Antioxidant
Antioxidant Icon
AntioxidantAntioxidant Icon

Ergothioneine is an antioxidant.

Benzylidene Dimethoxydimethylindanone Skin Protecting

We don't have a description for Benzylidene Dimethoxydimethylindanone.

Unknown Full details ->
Arabidopsis Thaliana Extract Antioxidant
Antioxidant Icon
AntioxidantAntioxidant Icon

Arabidopsis Thaliana Extract is an antioxidant.

Unknown Full details ->
Carnosine Skin Conditioning

We don't have a description for Carnosine.

Camellia Sinensis Leaf Extract Antimicrobial, Antioxidant, Astringent
Antioxidant IconHelps reduce Skin Redness IconHelps reduce irritation IconGood for Minimizing Pores IconHelps with Anti-Aging IconHelps fight Acne Icon
AntioxidantAntioxidant Icon 5 Benefits

Camellia Sinensis Leaf Extract is derived from the leaves of the tea plant. Black tea, green tea, and oolong tea are all harvested from this plant.

Vitis Vinifera Seed Extract Antimicrobial, Antioxidant, Skin Protecting
Antioxidant Icon
AntioxidantAntioxidant Icon

Vitis Vinifera Seed Extract comes from the grape vine. Grape seeds are a byproduct of creating grape juice or wine.

Theobroma Cacao Seed Extract Antioxidant
Antioxidant Icon
AntioxidantAntioxidant Icon

Theobroma Cacao Seed Extract comes from the Theobroma cacoa, or Cacao tree. Cacao trees are native to tropical landscapes.

Curcuma Longa Root Extract Masking, Perfuming
Fragrance Icon
FragranceFragrance Icon

Curcuma Longa Root Extract is from the spice, turmeric. Besides being a healthy and delicious spice, turmeric also has plenty of skincare benefits. It has anti-inflammatory, antioxidant, and anti-microbial properties.

Olea Europaea Fruit Extract Bleaching, Skin Conditioning

Olea Europaea Fruit Extract is extract from the olive fruit.

Unknown Full details ->
Euterpe Oleracea Fruit Extract

This extract comes from the Cabbage Palm, AKA the Açaí berry! It has skin soothing, antioxidant, and anti-aging properties.

Trifluoroacetyl Tripeptide-2 Skin Conditioning, Skin Protecting
Peptide Icon
PeptidePeptide Icon

Trifluoroacetyl Tripeptide-2 is a peptide.

Buddleja Officinalis Flower Extract UV Filter

We don't have a description for Buddleja Officinalis Flower Extract.

Unknown Full details ->
Coffea Arabica Leaf Cell Extract Antioxidant
Antioxidant Icon
AntioxidantAntioxidant Icon

Coffea Arabica Leaf Cell Extract is an antioxidant.

Unknown Full details ->
Crocus Sativus Leaf Cell Culture Extract Skin Protecting

We don't have a description for Crocus Sativus Leaf Cell Culture Extract.

Unknown Full details ->
Superoxide Dismutase Antioxidant, Skin Conditioning
Antioxidant Icon
AntioxidantAntioxidant Icon

Superoxide Dismutase is found in all living cells. This ingredient is AKA as 'SOD'.

Ubiquinone Antioxidant, Skin Conditioning
Antioxidant IconHelps with Anti-Aging Icon
AntioxidantAntioxidant Icon Helps with Anti-AgingHelps with Anti-Aging Icon

Ubiquinone (Coenzyme Q10) is a molecule already found in our bodies. It is a potent antioxidant and skin-soothing ingredient.

Zingiber Officinale Root Extract Masking, Skin Conditioning, Tonic

Zingiber Officinale is more commonly known as ginger.

Ceramide NP Skin Conditioning
Ceramide IconHelps hydrate Dry Skin IconHelps reduce Skin Redness IconHelps reduce irritation IconHelps with Anti-Aging Icon
CeramideCeramide Icon 4 Benefits

Ceramide NP is a type of ceramide.

Ceramide AP Skin Conditioning
Ceramide IconHelps hydrate Dry Skin IconHelps reduce Skin Redness IconHelps reduce irritation IconHelps with Anti-Aging Icon
CeramideCeramide Icon 4 Benefits

Ceramide AP is a type of Ceramide.

Ceramide EOP Skin Conditioning
Ceramide IconHelps hydrate Dry Skin IconHelps reduce Skin Redness IconHelps reduce irritation IconHelps with Anti-Aging Icon
CeramideCeramide Icon 4 Benefits

Ceramide EOP is a type of Ceramide.

Linoleic Acid Cleansing, Emollient, Skin Conditioning
Helps hydrate Dry Skin IconMay worsen Oily Skin IconBad for Acne Prone Skin IconNot safe for Fungal Acne Icon
Helps hydrate Dry SkinHelps hydrate Dry Skin Icon 3 Concerns

Linoleic Acid is Vitamin F and a fatty acid. It is an emollient and helps thicken texture. Linoleic acid helps with hydrating skin and nourishing the skin's barrier. The top layer of skin, or epidermis, contains high amounts of linoleic acid naturally.

Linolenic Acid Cleansing, Emollient, Perfuming
Fragrance IconNot safe for Fungal Acne Icon
FragranceFragrance Icon Not safe for Fungal AcneNot safe for Fungal Acne Icon

Linolenic Acid is a fatty acid. Our bodies need to consume this to use it. Linolenic Acid helps condition and restore skin. It is also used to treat inflammation and hyperpigmentation.

Sea Whip Extract Skin Conditioning

We don't have a description for Sea Whip Extract.

Bisabolol Masking, Skin Conditioning, Soothing
Helps reduce irritation Icon
Helps reduce irritationHelps reduce irritation Icon

Bisabolol is pimarily used to add fragrance to a product. However, it is also famous for helping soothe skin.

Tocopherol Antioxidant, Masking, Skin Conditioning
0-3 / 0-3 Vitamin E IconAntioxidant IconHelps hydrate Dry Skin IconHelps with Anti-Aging IconGood for Scar Healing IconHelps brighten skin IconMay cause irritation Icon
Vitamin EVitamin E Icon AntioxidantAntioxidant Icon 4 Benefits May cause irritationMay cause irritation Icon

Tocopherol (also known as Vitamin E) is a common antioxidant used to help protect the skin from free-radicals and strengthen the skin barrier. It's also fat soluble - this means our skin is great at absorbing it.

0-3 Com. / 0-3 Irr.
Tocopheryl Acetate Antioxidant, Skin Conditioning
0 / 0 Vitamin E IconAntioxidant IconHelps brighten skin Icon
Vitamin EVitamin E Icon AntioxidantAntioxidant Icon Helps brighten skinHelps brighten skin Icon

Tocopheryl Acetate is AKA Vitamin E. It is an antioxidant and protects your skin from free radicals. Free radicals damage the skin by breaking down collagen.

0 Com. / 0 Irr.
Cholesterol Emollient, Emulsifying, Skin Conditioning
0 / 0 Helps hydrate Dry Skin IconHelps reduce Skin Redness Icon
2 Benefits

Cholesterol is a class of organic molecules called lipids. It helps hydrate your skin and is essential to having a healthy skin barrier.

0 Com. / 0 Irr.
Phytosphingosine Skin Conditioning

Phytosphingosine is a phospholipid naturally found in our skin. It helps moisturize, soothe, and protect skin.

Jojoba Esters Emollient, Moisturising, Skin Conditioning
Not safe for Fungal Acne Icon
Not safe for Fungal AcneNot safe for Fungal Acne Icon

Jojoba Esters is a wax created from Jojoba oil. It is an emollient and film-forming ingredient. In bead form, it is an exfoliator.

Disliked Full details ->
Sodium PCA Humectant, Skin Conditioning
0 / 0

Sodium PCA is the sodium salt of pyroglutamic acid and is naturally occurring on human skin.

0 Com. / 0 Irr.
Pentylene Glycol 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.

Methyl Gluceth-20 Humectant, Moisturising

Methyl Gluceth-20 is a humectant. Humectants help draw moisture from the air to your skin.

Glycerin Humectant, Skin Conditioning, Skin Protecting
0 / 0 Helps hydrate Dry Skin IconHelps brighten skin Icon
2 Benefits

Glycerin is already naturally found in your skin. It helps moisturize and protect your skin.

0 Com. / 0 Irr.
Helianthus Annuus Seed Wax Skin Conditioning
Not safe for Fungal Acne Icon
Not safe for Fungal AcneNot safe for Fungal Acne Icon

Helianthus Annuus Seed Wax is created from the common sunflower.

Disliked Full details ->
Acacia Decurrens Flower Wax Emollient, Skin Conditioning
Not safe for Fungal Acne Icon
Not safe for Fungal AcneNot safe for Fungal Acne Icon

Acacia Decurrens Flower Wax isn't fungal acne safe.

Unknown Full details ->
Lecithin Emollient, Emulsifying, Skin Conditioning

Lecithin is a term for a group of substances found in plants, animals, and humans. They are made up of mixture of fatty acids. These fatty acids usually are a mixture of phosphoric acid's choline ester connected to stearic, oleic, and palmitic acids. Most lecithins are created from plant ingredients scuh as sunflower.

Disliked Full details ->
Sodium Lauroyl Lactylate Emulsifying

Sodium Lauroyl Lactylate is the lauric acid sodium salt of lactyl lactate.

Dicetyl Phosphate Emulsifying

We don't have a description for Dicetyl Phosphate.

Unknown Full details ->
Propanediol Dicaprylate/Caprate Emollient

We don't have a description for Propanediol Dicaprylate/Caprate.

Unknown Full details ->
Polyglycerin-3 Humectant

Polyglycerin-3 is a 3-unit glycerin polymer.

Ceteth-20 Phosphate Cleansing

We don't have a description for Ceteth-20 Phosphate.

Unknown Full details ->
Diisostearyl Malate Emollient, Skin Conditioning

Diisostearyl Malate is an emollient and most often used in lip products. It comes from isostearyl alcohol, a fatty acid, and malic acid, an AHA.

Xanthan Gum 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.

Disliked Full details ->
Steareth-2 Emulsifying
2 / 2

Steareth-2 is a waxy compound used to emulsify ingredients. It is created from polyethylene glycol and stearyl alcohol.

2 Com. / 2 Irr.
Very Disliked Full details ->
Acacia Senegal Gum Masking

We don't have a description for Acacia Senegal Gum.

Disliked Full details ->
Carbomer Emulsion Stabilising, Gel Forming
1 / 0

Carbomer is a polymer of acrylic acid. Its main role is to create gel consistency within products.

1 Com. / 0 Irr.
Disliked Full details ->
Acrylates/C10-30 Alkyl Acrylate Crosspolymer Emulsion Stabilising

Acrylates/C10-30 Alkyl Acrylate Crosspolymer is a synthetic polymer. It is used to thicken and improve the texture of products.

Disliked Full details ->
Dextran

We don't have a description for Dextran.

Unknown Full details ->
Sodium Hydroxide Buffering

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.

Citric Acid Buffering, Masking
AHA IconGood for Skin Texture IconGood for Minimizing Pores IconGood for Scar Healing IconHelps brighten skin IconMay cause irritation IconMay worsen Rosacea Icon
AHAAHA Icon 4 Benefits 2 Concerns

Citric Acid is an AHA derived from citrus fruits (think oranges, lemons, and limes!).

Disliked Full details ->
Disodium EDTA

Disodium EDTA plays a role in making products more stable by aiding other preservatives.

Disliked Full details ->
Ethylhexylglycerin Skin Conditioning

Ethylhexylglycerin (we can't pronounce this either) is commonly used as a preservative and skin softener. It is derived from glyceryl.

Phenoxyethanol Preservative
Preservative Icon
PreservativePreservative Icon

Phenoxyethanol is a preservative that has germicide, antimicrobial, and aromatic properties. Studies show that phenoxyethanol can prevent microbial growth. By itself, it has a scent that is similar to that of a rose.

Very Disliked Full details ->

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

Skin Conditioning, Solvent
Loved

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. Stay hydrated!

Learn more about Water
Humectant, Masking, Skin Conditioning
Mixed

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

  • It is a solvent, meaning that it helps to dissolve other ingredients. This also enhances the absorption of the product into one's skin.
  • It is a humectant, which means that it helps attract moisture into the skin.
  • It helps improve product application.

Overall, Butylene Glycol is a safe and well-rounded ingredient. It is unlikely to irritate skin, and works well with pretty much all other ingredients.

Humectant, Skin Conditioning, Skin Protecting
Loved

Glycerin is already naturally found in your skin. It helps moisturize and protect your skin.

A study from 2016 found glycerin to be more effective as a humectant than AHAs and hyaluronic acid.

As a humectant, it helps the skin stay hydrated by pulling moisture to your skin. The low molecular weight of glycerin allows it to pull moisture into the deeper layers of your skin.

Hydrated skin improves your skin barrier; Your skin barrier helps protect against irritants and bacteria.

Glycerin has also been found to have antimicrobial and antiviral properties. Due to these properties, glycerin is often used in wound and burn treatments.

In cosmetics, glycerin is usually derived from plants such as soybean or palm. However, it can also be sourced from animals, such as tallow or animal fat.

This ingredient is organic, colorless, odorless, and non-toxic.

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

Learn more about Glycerin
Skin Conditioning, Solvent
Mixed

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 help thicken or emulsify a product. Emulsifiers help stabilize a product. It does this by preventing certain ingredients from separating.

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
Antioxidant, Masking, Skin Conditioning
Liked

Tocopherol (also known as Vitamin E) is a common antioxidant used to help protect the skin from free-radicals and strengthen the skin barrier. It's also fat soluble - this means our skin is great at absorbing it.

Vitamin E also helps keep your natural skin lipids healthy. Your lipid skin barrier naturally consists of lipids, ceramides, and fatty acids. Vitamin E offers extra protection for your skin’s lipid barrier, keeping your skin healthy and nourished.

Another benefit is a bit of UV protection. Vitamin E helps reduce the damage caused by UVB rays. (It should not replace your sunscreen). Combining it with Vitamin C can decrease sunburned cells and hyperpigmentation after UV exposure.

You might have noticed Vitamin E + C often paired together. This is because it is great at stabilizing Vitamin C. Using the two together helps increase the effectiveness of both ingredients.

There are often claims that Vitamin E can reduce/prevent scarring, but these claims haven't been confirmed by scientific research.

Learn more about Tocopherol
Emollient, Emulsifying, Skin Conditioning
Disliked

Lecithin is a term for a group of substances found in plants, animals, and humans. They are made up of mixture of fatty acids. These fatty acids usually are a mixture of phosphoric acid's choline ester connected to stearic, oleic, and palmitic acids. Most lecithins are created from plant ingredients scuh as sunflower.

Lecithin is an emollient. Emollients help soften the skin and creates a barrier to keep moisture in.

As an emulsifier, it also helps prevent water and oil ingredients from separating. Lecithin can help ingredients be better absorbed by the skin. The phospholipids in Lecithin can produce liposomes. Liposomes help other ingredients get through the skin barrier.

Learn more about Lecithin
Masking, Skin Conditioning, Soothing
Loved

Bisabolol is pimarily used to add fragrance to a product. However, it is also famous for helping soothe skin.

Bisabolol comes from German chamomile essential oil. Synthetic Bisabolol has been shown to be less effective.

Bisabolol helps soothe skin. It does this by blocking the inflammatory signals, helping to reduce your body's reaction to irritation.

Bisabolol also interferes with the process of hyperpigmentation. This can help with reducing dark spots and uneven tone.

Bisabolol is an antioxidant. Antioxidants help fight free-radicals. Free-radicals are molecules that may damage your skin cells. By fighting these free-radicals, Bisabolol may slow down signs of aging.

Studies have shown Bisabolol to have antimicrobial properties and may be a fungicide. These properties help preserve a product's shelf life.

Bisabolol also helps the absorption of other ingredients.

Learn more about Bisabolol
Buffering
Mixed

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.

Learn more about Sodium Hydroxide
Preservative
Very Disliked

Phenoxyethanol is a preservative that has germicide, antimicrobial, and aromatic properties. Studies show that phenoxyethanol can prevent microbial growth. By itself, it has a scent that is similar to that of a rose.

It's often used in formulations along with Caprylyl Glycol to preserve the shelf life of products.

Skin Conditioning
Mixed

Ethylhexylglycerin (we can't pronounce this either) is commonly used as a preservative and skin softener. It is derived from glyceryl.

You might see Ethylhexylglycerin often paired with other preservatives such as phenoxyethanol. Ethylhexylglycerin has been found to increase the effectiveness of these other preservatives.

Ingredient Ratings

Here's what our community thinks of the ingredients in these products.

C15 Super Booster
10
6
4
1
liked
mixed
disliked
not rated
Alto Defense Serum
29
9
13
13
liked
mixed
disliked
not rated

When to use

304 Routines
88% use in am
13% use in pm
94% use every day
When to use See routines that use it ->
14 Routines
64% use in am
36% use in pm
100% use every day

Reviews

Here's what our community thinks

Paula's Choice C15 Super Booster 21 ingredients

4.5 /5
from 4 ratings
Absorbs Well (1) Expensive (1) Light (1)
Manateepiglet's avatar

Manateepiglet

2 months ago · Unsure Skin
Review

Makes my skin soft and absorbs well but it’s very expensive and smells like hot dog water

SkinBetter Science Alto Defense Serum 64 ingredients

2.0 /5
from 1 rating
Expensive (1) Irritating (1)
AideeCantu's avatar

AideeCantu

5 months ago · Sensitive Skin
Review

Don’t like how it doesn’t spread easily on face

Used daily for three days and it made me itchy

Cut back to every other day and it made my...

Don’t like how it doesn’t spread easily on face

Used daily for three days and it made me itchy

Cut back to every other day and it made my cheeks red and warm; it ended up breaking my skin barrier