A naturally occurring polyphenol antioxidant that displays a wide range of pharmacological activities, including antioxidant, anti-inflammatory, antimicrobial, anticancer, cardioprotective, neuroprotective, antidiabetic, anti-osteoporotic, estrogenic/antiestrogenic, anxiolytic, analgesic, and antiallergic activities. It reduces cell cycle progression in HT-29 cells. Kaempferol increases chromatin condensation, DNA fragmentation, and the number of early apoptotic cells in HT-29 cells in a dose-dependent manner. Besides, kaempferol increases the levels of cleaved caspase-9, caspase-3, and caspase-7 as well as those of cleaved poly (ADP-ribose) polymerase. Moreover, it increases mitochondrial membrane permeability and cytosolic cytochrome c concentrations.