Why do people often become smaller in height during later adulthood?

People often become smaller in height during later adulthood due to factors such as the compression of spinal discs, loss of bone density, and changes in posture. As individuals age, intervertebral discs can lose hydration and elasticity, leading to a decrease in disc height. Additionally, osteoporosis can weaken bones, making them more susceptible to fractures and contributing to a stooped posture. These changes collectively result in a noticeable reduction in overall height.