Siturins (SIRT1 - SIRT7) which remove acetyl tags from histones and other proteins which effects the packaging of DNA causing changes in gene expression. Nicotinamide adenine dinucleotide (NAD) is required for siturin activity. Sirtuins promote robustness during times of stress and can be protective against atherosclerosis, Alzheimerâs disease and osteoporosis, and cancer. Sirtuins function by the âgene Bâ mechanism. In humans, sirturins SIRT1, SIRT6, SIRT7 control the Epigenome and DNA Repair. SIRT3, SIRT4, SIRT5 are in the mitochondria where they control energy metabolism