You may be familiar with this: despite using a high-quality moisturiser, by the end of the day your skin feels tight and tired, and the fine lines around your eyes and mouth seem somehow more pronounced. We often tend to reach for more serums, but the condition of your skin is, first and foremost, a reflection of the processes taking place deep beneath its surface. It is precisely there that collagen, together with hyaluronic acid , plays a key role. How does this duo work in the body, and why shouldn’t we expect them to work miracles overnight? What happens to your skin after the age of 25? Collagen is the most abundant protein in the human body. It ensures that the skin remains firm, supple and retains its shape. However, from around the age of 25, the body’s natural production of collagen gradually declines. When collagen levels fall: The skin loses its elasticity and the first fine lines begin to form; the dermis (the deeper layer of the skin) becomes less able to retain moisture, and the skin appears