Skin science article
Olay Vitamin C + Peptide 24 Versus Olehenriksen Truth Serum
Olay Vitamin C + Peptide 24 Versus Olehenriksen Truth Serum This brightening moisturizer is formulated around Niacinamide and 3-O-Ethyl Ascorbic Acid to brighten dull-looking skin and soften the look of wrinkles. This brightening serum is formulated around Sod
Olay Vitamin C + Peptide 24 Versus Olehenriksen Truth Serum
This brightening moisturizer is formulated around Niacinamide and 3-O-Ethyl Ascorbic Acid to brighten dull-looking skin and soften the look of wrinkles.
This brightening serum is formulated around Sodium Ascorbyl Phosphate to brighten dull-looking skin.
What's inside
Key Ingredients
Benefits
Concerns
Ingredients Side-by-side
Water
Glycerin
Isohexadecane
Niacinamide
Dimethicone
Lactic Acid
Isopropyl Isostearate
Sodium Polyacryloyldimethyl Taurate
Stearyl Alcohol
3-O-Ethyl Ascorbic Acid
Palmitoyl Pentapeptide-4
Panthenol
Sodium Lactate
Trehalose
Cetearyl Glucoside
Cetearyl Alcohol
Behenyl Alcohol
Cetyl Alcohol
Stearic Acid
Palmitic Acid
Dimethiconol
PEG-100 Stearate
Sodium Benzoate
Parfum
Ascorbic Acid
Avena Sativa Peptide
Water, Glycerin, Isohexadecane, Niacinamide, Dimethicone, Lactic Acid, Isopropyl Isostearate, Sodium Polyacryloyldimethyl Taurate, Stearyl Alcohol, 3-O-Ethyl Ascorbic Acid, Palmitoyl Pentapeptide-4, Panthenol, Sodium Lactate, Trehalose, Cetearyl Glucoside, Cetearyl Alcohol, Behenyl Alcohol, Cetyl Alcohol, Stearic Acid, Palmitic Acid, Dimethiconol, PEG-100 Stearate, Sodium Benzoate, Parfum, Ascorbic Acid, Avena Sativa Peptide
Oleth-20
Sodium Ascorbyl Phosphate
Hydroxyethylcellulose
Phenoxyethanol
Caprylyl Glycol
Hexylene Glycol
Citric Acid
PEG-12 Dimethicone
Tocopheryl Acetate
Aroma
Hydrolyzed Vegetable Protein
Disodium Phosphate
Polysorbate 60
Aloe Barbadensis Leaf Extract
Citrus Aurantium Dulcis Fruit Extract
Sodium Hyaluronate
Thioctic Acid
Calcium Ascorbate
Sodium Phosphate
Sorbitol
Citrus Grandis Seed Extract
Camellia Sinensis Leaf Extract
Euphrasia Officinalis Extract
Rosa Canina Fruit Extract
Leuconostoc/Radish Root Ferment Filtrate
Potassium Sorbate
Triacetin
Sodium Benzotriazolyl Butylphenol Sulfonate
Benzyl Benzoate
Limonene
Linalool
CI 15985
Water, Glycerin, Oleth-20, Sodium Ascorbyl Phosphate, Hydroxyethylcellulose, Phenoxyethanol, Caprylyl Glycol, Hexylene Glycol, Citric Acid, Parfum, PEG-12 Dimethicone, Tocopheryl Acetate, Aroma, Hydrolyzed Vegetable Protein, Disodium Phosphate, Polysorbate 60, Aloe Barbadensis Leaf Extract, Citrus Aurantium Dulcis Fruit Extract, Sodium Hyaluronate, Thioctic Acid, Calcium Ascorbate, Sodium Phosphate, Sorbitol, Citrus Grandis Seed Extract, Sodium Benzoate, Ascorbic Acid, Camellia Sinensis Leaf Extract, Euphrasia Officinalis Extract, Rosa Canina Fruit Extract, Leuconostoc/Radish Root Ferment Filtrate, Potassium Sorbate, Triacetin, Sodium Benzotriazolyl Butylphenol Sulfonate, Benzyl Benzoate, Limonene, Linalool, CI 15985
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.
Ascorbic Acid is is pure Vitamin C and is the biologically active form used directly by skin.
Not only is vitamin C great for your overall health and immune system, but it also has plenty of benefits for your skin. It is best supported by academic literature for:
Topical vitamin C has been shown to help neutralize oxidative stress from UV and pollution, helping to improve photoaging and hyperpigmentation when used consistently.
One clinical study found that using 5% topical vitamin C for six months improved signs of photodamaged skin, both on the surface and in the deeper structural layers of the skin.
While vitamin C doesn’t replace sunscreen, studies show it can boost photoprotection when combined with Vitamin E and ferulic acid. These two ingredients help improve stability and protective effects.
The big downside of this ingredient is formulation difficulty. Vitamin C is prone to oxidation and doesn't penetrate the skin unless formulated correctly. Research found that vitamin C absorbs into the skin best at a low pH (< 3.5) with about 20% being the upper limit for effective absorption.
Skin levels can saturate after repeated application; this means your skin won’t keep absorbing more once it’s full of vitamin C. This is why more isn’t always better with vitamin C and why very high concentrations don’t necessarily give extra benefits.
Ascorbic acid generally works well with many skincare ingredients but can be irritating when combined with other active ingredients. Strong oxidizing acne treatments like benzoyl peroxide can reduce the effectiveness of vitamin C if they are used at the same time; they are often recommended for use at different times of day.
Read more about other types of Vitamin C:
Foods rich with vitamin C include oranges, strawberries, broccoli, bell peppers, and more. When consuming Vitamin C, your skin receives a portion of the nutrients.
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.
Parfum is a catch-all term for an ingredient or more that is used to give a scent to products.
Also called "fragrance", this ingredient can be a blend of hundreds of chemicals or plant oils. This means every product with "fragrance" or "parfum" in the ingredients list is a different mixture.
For instance, Habanolide is a proprietary trade name for a specific aroma chemical. When used as a fragrance ingredient in cosmetics, most aroma chemicals fall under the broad labeling category of “FRAGRANCE” or “PARFUM” according to EU and US regulations.
The term 'parfum' or 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term.
For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance by INCI standards.
One example is Calendula flower extract. Calendula is an essential oil that still imparts a scent or 'fragrance'.
Depending on the blend, the ingredients in the mixture can cause allergies and sensitivities on the skin. Some ingredients that are known EU allergens include linalool and citronellol.
Parfum can also be used to mask or cover an unpleasant scent.
The bottom line is: not all fragrances/parfum/ingredients are created equally. If you are worried about fragrances, we recommend taking a closer look at an ingredient. And of course, we always recommend speaking with a professional.
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.
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!