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, Alzheimer’s disease and osteoporosis, and cancer. Sirtuins function by the “gene B” mechanism. In humans, sirturins SIRT1, SIRT6, SIRT7 control the epigenmone and DNA Repair. SIRT3, SIRT4, SIRT5 are in the mitochondria where they control energy metabolism