The nucleus pulposus is the soft, gel-like center of an intervertebral disc in the spine. It is surrounded by a tougher outer layer called the annulus fibrosus. The nucleus pulposus helps absorb shock and provides flexibility to the spine, allowing for movement and support. This structure is primarily composed of water, collagen fibers, and proteoglycans, which give it its unique properties. As people age, the nucleus pulposus can lose hydration and elasticity, potentially leading to conditions like herniated discs or degenerative disc disease. Maintaining spinal health is essential for overall mobility and well-being.