Kaempferol is a natural flavonol, The SIRT1 member of sirtuin deacetylases has been shown, along with PGC-1α, to mediate the life span extension associated with caloric restriction. SIRT1 deacetylates protein substrates, thus altering their activity or function. SIRT1 interacts directly with PGC-1α to mediate gluconeogenesis and mitochondrial biogenesis by deacetylating and activating PGC-1α. The activators of SIRT1 polyphenols resveratrol and kaempferol have been shown to increase mitochondrial function and energy expenditure. Kaempferol had a stronger impact. It also attenuated the accumulation of the ageing marker lipofuscin, suggesting a life-prolonging activity of this flavonoid. Kaempferol has been identified in many plant species commonly used in traditional medicine. The enzyme kaempferol 4'-O-methyltransferase uses S-adenosyl methionine and kaempferol to produce S-adenosylhomocysteine and kaempferide.