Mitochondria are organelles found in cells that produce energy through oxidative phosphorylation. They play a key role in numerous cellular processes and are involved in aging. Mitochondrial biogenesis generates new mitochondria and regulates mitochondrial content in cells. During aging, mitochondrial function declines which can negatively impact organ function. Mitochondrial alterations are seen in aging tissues and are associated with mutations, dysfunction, and inflammation. Supporting mitochondrial biogenesis and function through diet, exercise, and supplements may help prevent age-related diseases and support healthy aging.