I Energy, evolution and medicine 1 Energy and the body.- 2 Evolutionary medicine.- 3 The brain and the immune system - two competing realms.- II Energy expenditure in the spotlight 4 Inflammation and energy.- 5 Pain and energy.- 6 Psychological stress and energy.- 7 Other energy-draining situations.- 8 What does increased energy expenditure mean for the body.- III From energy and evolution to symptoms 9 Daytime tiredness and depression.- 10 Sleep disorders and symptoms related to the time of day.- 11 Loss of appetite - malnutrition and malnutrition.- 12 Muscle wasting.- 13 Bone loss - osteoporosis.- 14 Weight changes (increase and decrease).- 15 Storage hormones (increase and decrease). 11 Loss of appetite, malnutrition and malnutrition.- 12 Muscle atrophy.- 13 Bone atrophy - osteoporosis.- 14 Weight changes (gain and loss).- 15 The storage hormone insulin doesn't do it - insulin resistance.- 16 Dwindling libido, lower fertility.- 17 The sympathetic nervous system fires the insulin hormone. 17 Sympathetic nervous system fires and causes high blood pressure.- 18 Increased blood clotting - thromboses/embolisms.- 19 Stress worsens inflammation and inflammation changes stress resilience.- 20 The big summary: unwanted energy expenditure.- Glossary.- Appendix.