La Roche-Posay Hydraphase HA Light Hyaluronic Acid Face Moisturizer Versus La Roche-Posay Hydraphase HA Rich Hyaluronic Acid Face Cream

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.

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

Like hyaluronic acid, it is great at holding water and acts as a humectant. This makes it a great skin hydrating ingredient.

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.

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.

Hydrolyzed Hyaluronic Acid is a form of hyaluronic acid. It is created by the hydrolysis of hyaluronic acid with a high molecular weight. Once created, Hydrolyzed Hyaluronic Acid has a low molecular weight.

Low molecular weight HA has been shown to hydrate and increase elasticity of the skin. Increasing elasticity is also associated with reduction of wrinkle depth.

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.

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.

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.

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.