Cleansers are designed to do something that sounds simple: remove dirt, excess oil, makeup and other substances from the skin. But there is a trade-off.

Sunscreen is one of the most familiar skincare products, yet the science behind it is surprisingly complex. One of the most common questions is whether mineral sunscreen or chemical sunscreen is better. The answer is not quite that simple. Both types can protect the skin from ultraviolet radiation, but they use different types of UV filters and behave differently within a cosmetic formulation.

When we buy a skincare product, we naturally expect it to look, smell and feel the same from the first use to the last. A cream should not suddenly become watery. A serum should not turn a completely different colour. And a product that was perfectly pleasant to use when it was opened should not gradually develop an unusual smell.

A cosmetic cream may look simple when you use it. You scoop out a little, spread it on your skin, and it disappears into a smooth layer. But making that cream is a surprisingly complex process.

Preservatives are one of those cosmetic ingredients that often receive a bad reputation. You may see products advertised as “preservative-free” and naturally wonder: if preservatives are unnecessary, why are they used in the first place?

When we apply a serum or cream, it is tempting to imagine the active ingredients simply travelling into the skin and getting to work. But the skin is not an open surface.

When your skin feels dry, the obvious solution seems simple: use a moisturizer. But what does a moisturizer actually do? It turns out that “moisturizing” is not one single process. Different ingredients work in different ways, and the best-performing products often combine several approaches. Some ingredients attract water, others help smooth the skin, while others reduce the amount of water that escapes from its surface.

The skin barrier is one of those skincare terms we hear everywhere. Products claim to “support the skin barrier,” ingredients are promoted as “barrier-friendly,” and damaged skin is often described as dry, tight or sensitive. But what actually is the skin barrier?

When developing a new skincare product, the active ingredients are often the first thing people talk about. A brand may start with a particular peptide, vitamin, botanical extract or other ingredient and build the product concept around it.

The story of Iconic French Cosmetics brands - L'Orèal, Caudalie and Yves Rocher