In chapter one it talks about how hemachromatosis is a hereditary disease and it’s the most common genetic disease for people of European descent, in which the body can't register that it has enough iron. So it keeps absorbing as much of it as possible, and this can have very, serious side effects (including death). Iron is very important for bacteria, cancer, and other things to grow. The way this disease is most easily treated is blood letting. Looks like all those crazy blood-letting, leech-sticking doctors weren't mistreating everyone. What is the author's argument for why this disease stuck around? To really simplify things: during the black plague in Europe, people with more iron in their system were more likely to die because bacteria feeds on iron. Women, children, and the elderly were less targeted than men. But people with hemachromatosis also happen to have white immune system blood cells with considerably less iron than the normal person, and this counteracted the precise way that the bubonic plague killed its victims - through their own immune system. Therefore, their immune system was actually able to fight off the bubonic plague, allowing them to live while 1/3 - 1/4 of the population died off. Even though hemachromatosis will eventually overload your system with iron, unabated, and cause you to die, it will save your life against normal infections. On the other hand, anemia has evolved because not having enough iron in your system means that it is hard for bacteria to live. While we do need iron, anemia has helped many populations avoid things like malaria.
Chapter 2 Summary
In chapter two it talks about how Diabetes is much more common in people of Northern European descent and very uncommon in people of purely African, Asian, and Hispanic descent. The Younger Dryas was an ice age that occurred 13,000 years ago. After many rounds of scientific research and revision, it was