Cellular senescence, discovered in 1961 by Leonard Hayflick and Paul Moorhead, is a state in which cells no longer perform their functions, instead emitting harmful chemicals that turn other cells senescent. Senescence is primarily caused by telomere shortening and DNA damage, and senescent cells are known to contribute to multiple diseases, such as Alzheimer’s, Parkinson’s, and dementia.
One method of removing senescent cells is caloric restriction, which is a temporary reduction of food calories. This has been shown to be one of the most effective methods to decrease and slow the onset of aging phenotypes [1].
This is related to autophagy, which is the cell’s natural method of breaking down parts of itself when it doesn’t have immediate access to food [2]. Autophagy has been shown to both promote and prevent senescence. It removes damaged macromolecules or organelles, such as mitochondria, which would otherwise cause cellular senescence. However, some of the processes that cause autophagy cause cellular senescence as well [3].