The term “skin-identical ingredients” or "skin-repairing ingredients" refers to the substances between skin cells (technically referred to as the intercellular matrix) that keep skin cells connected and help maintain skin’s fundamental external structure. Think of your skin as consisting of bricks, with the mortar being the material that holds these bricks together. Skin cells are the bricks, and the mortar (cement) between them is made up of skin-identical ingredients. An intact, stable, healthy, and strong mortar structure is what allows skin to look smooth, soft, moist, supple, and young.
Unfortunately, the mortar, especially in the external barrier of our skin, is easily compromised by sun damage (that’s the major culprit), irritation, overcleansing, overscrubbing, dry climate, air conditioning, indoor heaters, skin disorders, and on and on. When the skin’s mortar (the intercellular matrix) breaks down, water loss, flakiness, and inflexible, stiff, uncomfortable-feeling skin is the result. It is of vital importance for all skin types to maintain or restore the skin’s mortar (intercellular matrix) to help skin fight off environmental stresses and most certainly look younger.
These substances that keep skin intact are what we refer to as skin-identical ingredients. Antioxidants are one group of skin-identical ingredients but skin-identical ingredients also encompass an additional assortment of substances, such as ceramides, lecithin, glycerin, polysaccharides, hyaluronic acid, sodium hyaluronate, sodium PCA, amino acids, cholesterol, glycerol, phospholipids, glycosphingolipids, glycosaminoglycans, glycerides, fatty acids, and many, many more. All of these give skin what it needs to keep skin cells together. Just adding water alone can do nothing if the intercellular matrix is damaged. When a moisturizer contains a combination of these, it can help reinforce the skin’s natural ability to function normally, improve skin’s texture, fight environmental stress (sun, pollution, and more), and, along with antioxidants and cell-communicating ingredients, eliminate dry skin with regular use.