Kiehl's Auto-Tone Discoloration & UV Solution SPF 30 Versus La Roche-Posay Mela B3 UV SPF 30

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.

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.
• It has mild preservative properties.

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Silica is a mineral naturally found in our skin. It helps to thicken and smooth the texture of a product. It also acts as an agent for other ingredients by increasing the absorption of other ingredients into the skin.

Silica is often used for absorption and can help reduce shine when products are applied. Silica occurs in naturally in materials like clay and sandstone, and it can also be produced synthetically.

Titanium dioxide is known for its UVA and UVB protection properties. It is non-comedogenic and non-irritating. Titanium Dioxide is a physical sunscreen. Physical sunscreens reflect light and prevent it from reaching your skin.

Protecting your skin against UV radiation can prevent the signs of aging. Sun damage is associated with fine-lines, wrinkles, loss of firmness, and hyperpigmentation. Titanium dioxide can help prevent premature aging.

Hydroxyacetophenone is antioxidant with skin conditioning and soothing properties. It also boosts the efficiency of preservatives.

This ingredient is not irritating or sensitizing.

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate (long name, huh?) is a synthetic antioxidant.

It is used to help stabilize other antioxidants or prevent the color from changing in a product.

Potassium hydroxide is commonly known as caustic potash. It is used to fix the pH of a product or as a cleaning agent in soap. In cleansers, it is used for the saponification of oils.

Sapnification is the process of creating fatty acid metal salts from triglycerides and a strong base. During this process, Potassium Hydroxide is used up and is not present in the final product.

Sodium Thiosulfate is a type of sulfate.

Trisodium Ethylenediamine Disuccinate is used to help stabilize a product.

It is a chelating agent, meaning it helps prevent metal ions from binding to other ingredients. This prevents unwanted reactions in products. Metal ions can come into a product via the water ingredient. They are found in trace amounts and are not known to be harmful.

This ingredient is patented by L'Oreal and found in the Melasyl line of La Roche Posay.

According to L'Oreal, this ingredient is used to prevent UV-induced tanning and dark spots.

Butyrospermum Parkii Butter is a plant lipid from the fruit of the Shea Tree. It is an effective skin hydrator and emollient.

Emollients help soothe and soften your skin. It does this by creating a protective film on your skin. This barrier helps trap moisture and keeps your skin hydrated. Emollients may be effective at treating dry or itchy skin.

Ammonium Acryloyldimethyltaurate/Vp Copolymer (let's call it AAVC for short) is a synthetically created polymer. It's used as a film-forming agent and used to thicken the consistency of products.

AAVC is able to increase the consistency and viscosity of products due to its large molecule size. It also prevents ingredients from separating.

Arachidyl Alcohol is a fatty alcohol made from peanut oil. It is an emollient, emulsifier, and thickener.

You'll most likely find this ingredient as an emulsifier in water-based cosmetics.

We don't have a description for Arachidyl Glucoside yet.

A type of fatty alcohol. Fatty Alcohols are most often used as an emollient or to thicken a product. They are usually derived from natural fats and oils and therefore do not have the same drying or irritating effect as traditional alcohols.

Emollients help keep your skin soft and hydrated by creating a film that traps moisture in.

Caprylyl Glycol is a humectant and emollient, meaning it attracts and preserves moisture.

It is a common ingredient in many products, especially those designed to hydrate skin. The primary benefits are retaining moisture, skin softening, and promoting a healthy skin barrier.

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

A high amount of carbomer can cause pilling or balling up of products. Don't worry, most products contain 1% or less of carbomer.

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

As an AHA, Citric Acid removes the top layer of skin cells from the newer layer of skin underneath. This helps skin to remove dark spots and even out skin tone.

Mica refers to a group of silicate minerals. Mica crystals are easily split to give products a shimmer. These crystals are able to reflect light to temporarily give your skin a glowy look.

Mica is found to be safe. Trace amounts of heavy metals may be found in mica, but these metals are not harmful in our personal products.

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.

We don't have a description for Poly C10-30 Alkyl Acrylate yet.

Polyglyceryl-4 Caprate comes from Capric Acid and Polyglycerin-4. It is an emulsifier.

Emulsifiers help stabilize a product. They do this by preventing ingredients from separating, such as oils and water which do not mix naturally.

We don't have a description for Sodium Dilauramidoglutamide Lysine yet.

Tin Oxide is an inorganic oxide used to add opacity and volume to a product. In nature, it is already found in mineral form. The main ore of tin is an opaque and shiny mineral called casseterite.

Tin Oxide helps remove translucency in a product, or make it more opaque. Besides adding opacity, tin oxide is used for bulking to add volume.

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.

Ci 14700 is a synthetic red dye.

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.