“…290 Various genetic risk factors become active at various stages of life, some possibly during early CNS development 729 (presenilin may have a role in fetal neurogenesis 988 ) and some from later brain trauma 7 or chemical exposure [41][42][43]47 and may lead to initiation of the spiral cascade in Figure 15. 4,32 (2) Life-style-related risk factors such as antioxidant deficiency, 55 obesity, 35,36 hypercholesterolemia, 39,40 passivity, 57,61,56 and smoking 34,772 may aggravate these risk factors by challenging metabolic networks, the already weakened stress response, and overall neuronal capacity. They all relate to metal ion dyshomeostasis, notably via zinc, as discussed in section 7.…”