Polyglutamic acid, known to hold up to 10 times more water than hyaluronic acid, increases the natural moisturising factors on the top layers of the epidermis, forming a protective film to prevent dehydration and water loss. By focusing on hydrating the top layers of skin, polyglutamic acid plumps and smooths, helping to diminish the appearance of fine lines and wrinkles. This compares to hyaluronic acid, a naturally smaller molecule that penetrates the deeper layers of the epidermis. Using a combination of both acids promotes skin hydration and plumpness. Polyglutamic acid is known to inhibit the activity of hyaluronidase (an enzyme that degrades hyaluronic acid), which in turn improves skin tone, texture and reduces the signs of ageing.