Cetaphil Daily Defence Face Moisturiser With SPF 50+ - UK Versus La Roche-Posay Hydraphase UV Intense Light

Dimethicone is a type of synthetic silicone created from natural materials such as quartz.

What it does:

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

It is a chelating agent, meaning it neutralizes metal ions that may be found in a product.

Drometrizole Trisiloxane is a UV filter that provides both UV-A (344 nm) and UV-B (303 nm) protection.

This ingredient is photostable and studies show it to be generally safe and effective. The compound Meroxyl XL is owned by L'Oreal while Drometrizole trisiloxane can be found in other sunscreen brands.

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.

Glyceryl Stearate is a mix of glycerin and stearic acid.

It is used to stabilize the mixing of water and oil ingredients. By preventing these ingredients from separating, it can help elongate shelf life. It can also help thicken the product's texture.

Octocrylene protects skin from sun damage. It absorbs UV-B with peak absorption of 304 nm. It is a common sunscreen ingredient and often paired with avobenzone, a UVA filter. This is because octocrylene stabilizes other sunscreen ingredients by protecting them from degradation when exposed to sunlight. Octocrylene is a photostable ingredient and loses about 10% of SPF in 95 minutes.

Octocrylene also acts as an emollient, meaning it helps skin retain moisture and softens skin. It is oil-soluble and hydrophobic, enhancing water-resistant properties in a product.

Peg-100 Stearate is an emollient and emulsifier. As an emollient, it helps keep skin soft by trapping moisture in. On the other hand, emulsifiers help prevent oil and water from separating in a product.

PEGS are a hydrophilic polyether compound . There are 100 ethylene oxide monomers in Peg-100 Stearate. Peg-100 Stearate is polyethylene glycol ester of stearic acid.

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.

Potassium Cetyl Phosphate is the potassium salt of a mixture. This mixture consists of the esters from phosphoricacid and cetyl alcohol.

Potassium Cetyl Phosphate is an emulsifier and cleansing agent. Emulsifiers help stabilize a product. It does this by preventing certain ingredients from separating.

Propylene Glycol is an odorless, colorless liquid. As a humectant, it helps skin retain moisture. It also aids in delivering active ingredients.

Another role of this ingredient is preventing a product from melting or freezing. Propylene glycol also adds antimicrobrial properties to a product, elongating product lifespan.

Stearic Acid is a fatty acid. It is an emollient, emulsifier, and texture enhancer.

As an emollient, stearic acid helps soften skin. It aids the skin's protective barrier by preventing water loss. It also provides a gentle cleansing effect without stripping away natural oils.

Stearyl Alcohol is a type of fatty alcohol from stearic acid. It is a white, waxy compound used to emulsify ingredients.

Fatty Alcohols are most often used as an emollient or to thicken a product. Emollients help soothe and hydrate the skin by trapping moisture.

Ecamsule is a UV-A absorber (290–400 nm) patented by L'Oreal. It is derived from benzylidene camphor, making it highly photostable.

Ecamsule is able to prevent UV from reaching the skin. It absorbs UV and releases it as thermal energy.

Triethanolamine is an emulsifier and pH adjuster. It is created using ethylene oxide and ammonia. This gives Triethanolamine a nitrogen core and a similar scent to ammonia.

As an emulsifier, it prevents ingredients from separating and enhances texture by adding volume to a product.

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.