Is It True That Insulin Makes You Age Faster Or Is It Just More Dieting Mumbo Jumbo?
Yes. In fact, calorie restriction induces a reduction in the insulin signalling pathways (both through IGF-I and insulin), and this reduction in insulin signalling pathways is thought to be one of the primary mechanisms through which calorie restriction acts to increase lifespan. High blood insulin levels are usually the result of high blood glucose levels. So high levels of insulin signalling are a signal of high "nutritional state", and shift a cell's internal state towards increased levels of growth and decreased levels of repair. Increases in growth and decreases in repair = increases in waste products that accumulate within a cell and that ultimately cause aging at the cellular level. An increase in insulin levels usually causes an increases in protein synthesis and decreases in both proteolysis and autophagy through the pathway diagrammed below . This is bad, as this will effectively increase the number of misfolded proteins that fail to degrade (one major factor in aging rate). In fact, decreased protein synthesis and increased autophagy are both associated with increased lifespan (Page on Nih, Protein translation, 2007. ). (figure from ) For a summary of its physiologica Continue reading >>