Our cells constantly clean up the cellular garbage and recycle their components This process is called autophagy which is the biological process taking care of this cellular cleanup.
One of the main hallmarks of ageing is increased cellular senescence. These are the cells that have reached the end of their lifespan but don’t die. Senescent also known as Zombie cells accumulate with age.
Chronic inflammation and the exhaustion of stem cells are thought to be the most significant consequences of senescence in ageing tissues.