Cell turnover refers to the process by which old or damaged cells are replaced by new ones. This natural cycle is essential for maintaining healthy tissues and organs in the body. Different types of cells have varying turnover rates; for example, skin cells regenerate approximately every 28 days, while red blood cells have a lifespan of about 120 days. Factors such as age, diet, and overall health can influence the rate of cell turnover. Stem cells play a crucial role in this process, as they can differentiate into various cell types to replace those that are lost. Efficient cell turnover is vital for healing and maintaining optimal function in the body.