While fine lines, wrinkles and lax skin are all symptoms of the natural aging process, the main culprit behind these signs of aging is the gradual depletion of a protein found in the skin known as collagen. Collagen is what gives your skin it’s structure during your youth, keeping it smooth and firm. But as you age, collagen production gradually decreases, and the result is a loss of skin elasticity and strength. When the skin loses its elasticity, or ability to bounce back, it becomes saggy and loose in appearance, especially along the jawline and neck.