why do we need sleep

We need sleep because it is essential for the body's and brain's repair, restoration, and proper functioning. Sleep allows the brain to clear out toxic waste, strengthen important neural connections, and reorganize nerve cells to support learning, memory, creativity, and decision-making. It also plays a critical role in conserving energy, repairing cells and tissues, regulating hormones including those involved in metabolism and immune function, and supporting heart health. Lack of sleep impairs concentration, immune defense, and increases the risk for chronic diseases such as diabetes, cardiovascular disease, and obesity. Overall, sleep is vital for maintaining physical health, brain function, and emotional well-being. This is why humans spend about one- third of their lives sleeping and need to maintain regular, sufficient sleep to survive and thrive.