Vichy Aqualia Thermal UV Defense Moisturizer SPF 30 Ingredients Explained

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.

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.

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.

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.

Dimethicone is a silicone used for making products smooth and silky. It also has the added benefit of sealing in hydration. The amount of dimethicone found in beauty products is considered safe and non-comedogenic, meaning it won't clog pores.

Dimethicone has been found increase absorption in skin, boosting the benefits of other ingredients. While there is concern for the safety of dimethicone, the levels used in skincare are safe for use.

Niacinamide has emerged as an all-star ingredient due to its many benefits.

It is known to treat acne by reducing inflammation. It also helps fade dark-spots and strengthen the skin by promoting the growth of the ceramide barrier.

Peg-100 Stearate is an emollient and emulsifier. 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.

Peg-100 Stearate helps keep skin soft by trapping moisture in. It helps prevent oil and water from separating in a product. By binding oil and water, it helps remove dirt and oil to be rinsed away.

Glyceryl Stearate is a mix of glycerin and stearic acid.

Glyceryl Stearate 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.

We don't have a description for Mannose.

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.

Ceramide NP is a type of ceramide.

Ceramides are intercellular lipids naturally found in our skin that bonds dead skin cells together to create a barrier. They are known for their ability to hold water and thus are a great ingredient for dry skin.

Dimethicone/Vinyl Dimethicone Crosspolymer is a silicone used to improve the texture of products and absorb oil. It does not get absorbed into the skin.

Like other silicones, Dimethicone/Vinyl Dimethicone Crosspolymer helps condition the skin by creating a barrier. In this sense, it can act as an emollient and trap moisture in.

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.

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

The PCA stands for pyrrolidone carboxylic acid, a natural amino acid derivative.

Myristic Acid is a saturated fatty acid. It is naturally found in milk fat. Other sources include palm oil, coconut oil, and butter fat.

Myristic Acid is an emulsifer and cleanser. As an emulsifer, it stabilizes a product by preventing ingredients from separating. Myristic Acid helps clean your skin by acting as a surfactant. It tends to gather oil and dirt on your skin to be easily rinsed away.

Palmitic Acid is a fatty acid found in our skin. In cosmetics, it is usually derived from palm oil. It is a cleanser, emollient, and emulsifier.

As an emollient, it helps hydrate the skin. The emulsifying properties keep ingredients together in a product.

Ammonium Polyacryloyldimethyl Taurate is a polymer made from ammonium salts. It helps add stability and texture to a product.

Ammonium Polyacryloyldimethyl Taurate is stable over a wide pH range. Due to its ability to absorb water, it can help thicken the texture of a product.

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.

Capryloyl Glycine is created by adding an acyl group to glycine and caprylic acid chloride.

It is a cleanser due to its surfactant properties. Surfactants help dirt, oil, and other polluants be more easily rinsed away. According to manufacturers, Capryloyl Glycine also helps soften the skin and regulate sebum production.

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.

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.

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.

Cetyl Alcohol is a fatty alcohol. Fatty Alcohols are most often used as an emollient or to thicken a product.

Cetyl Alcohol is not related to SD alcohol, denatured alcohol, or ethyl alcohol. The FDA allows products labeled "alcohol-free" to have fatty alcohols.

Parfum is a catch-all term for an ingredient or more that is used to give aroma to products. Parfum, or fragrance, 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.

In the US, the alternative name for parfum is 'fragrance'. The term 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term.