title: Why do we grow old?
mesh_terms: D000368:Aged; D000375:Aging; D000596:Amino Acids / Q000378:metabolism; D001323:Autoantibodies / Q000009:adverse effects; D001683:Biological Clocks; D004247:DNA / Q000096:biosynthesis; D005609:Free Radicals; D006801:Humans
chemical_list: D000596:Amino Acids; D001323:Autoantibodies; D005609:Free Radicals; D004247:DNA