I really enjoyed reading Survival of the Sickest: A Medical Maverick Discovers Why We Need Disease. Dr. Maolem explains how the diseases we suffer from have helped us survive in the past. For example, people with hemochromatosis were more likely to survive the plague. (Bacteria needs iron to survive and while people with hemochromatosis have lots of iron in their blood, they don't have any in their macrophages.) They died early due to their disease but after their child bearing years so the disease, and its advantages and disadvantages, were passed along.
He theorizes that diabetes might have helped people survive a mini ice age – sugar lowered the freezing temperature of blood.
Like good teachers, Dr. Maolem and his co-author Jonathan Prince use a lot of interesting anecdotes and facts to make the material easy to relate to and memorable. (Did you know Inuit hunters can raise the temperature of the skin on their hands from freezing to fifty degrees in minutes? And do so periodically when they are outside?)
You may or may not end up agreeing with all of Dr. Maolem's theories, but if you like understanding why and how the human body and evolution work, you'll probably enjoy Survival of the Sickest.