Survival of the Sickest (book)

Cover of Survival of the Sickest

Survival of the Sickest: A Medical Maverick Discovers Why We Need Disease is a popular science book written by Dr. Sharon Moalem with Jonathan Prince. The book explores the paradoxical idea that some diseases, which are often seen as purely detrimental, may have evolved because they offer certain survival advantages. It was first published in 2007.

Overview

Survival of the Sickest delves into the concept of evolutionary medicine, examining how certain genetic traits that predispose individuals to diseases may have been beneficial in the past. The book is structured around several key examples that illustrate this concept, drawing on a wide range of scientific disciplines including genetics, epidemiology, and anthropology.

Key Concepts

Iron and Infection

One of the central themes of the book is the role of iron in the human body and its relationship with infectious diseases. The author discusses how the regulation of iron levels can influence susceptibility to infections. For instance, the genetic disorder hemochromatosis, which causes iron overload, may have provided a survival advantage during the bubonic plague by depriving bacteria of the iron they need to thrive.

Diabetes and Cold Climates

The book also explores the hypothesis that type 1 diabetes may have been advantageous in cold climates. The author suggests that the increased blood sugar levels associated with diabetes could have acted as an antifreeze, helping individuals survive in extremely cold environments.

Sickle Cell Anemia and Malaria

Another example discussed is sickle cell anemia, a genetic condition that provides resistance to malaria. The sickle-shaped red blood cells in carriers of the sickle cell trait are less hospitable to the malaria parasite, offering a protective effect in regions where malaria is prevalent.

Lactose Tolerance

The book examines the evolution of lactose tolerance in certain human populations. The ability to digest lactose into adulthood is linked to the domestication of dairy animals and the nutritional benefits of milk consumption, illustrating how cultural practices can drive genetic evolution.

Impact and Reception

Survival of the Sickest was well-received for its engaging writing style and its ability to make complex scientific concepts accessible to a general audience. It has been praised for its thought-provoking insights into the relationship between disease and evolution, challenging readers to reconsider the role of illness in human history.

Related Pages

• Evolutionary medicine
• Genetic disorder
• Natural selection
• Human evolution