Survival of the sickest

A Medical Maverick discovers why we need diseases
Dr. Sharon Moalem
Jonathan Prince

Just started this but straightaway a recommedation. This book talks about something that many of us realise intrisically - that sickness and disease is by itself a very complex operation of the body and the pathogen. What this does is try to look at the root of our diseases froman evolutionary point of view. The central tenet that this starts from is quite simple - If evolution weeds out the undesirable trait over generations, why is it that certain hereditary mass killers still remain? The strongest case in point - Diabetes or for that matter obesity. Why is it that evolution has still not found a way out for these or to be more exact, why havent our bodies evolved to make us resistant to diabetes and obesity?
What he does move in to do then is to track the history of these hereditary conditions. Starting from Hemochromatis (excess absorption of iron by the body) to Diabetes and moving on to the other hereditary conditions.
Taking the case of diabetes, his postualation is that the current conditions of diabetes might be an evolutionary response to the rapid freezing during ice ages wherein the body would have to increase the sugar concentration in the body to avoid the effects of freezing. While it makes for good enjoyable reading, it still begs many questions.

a. why is that diabetes is prevalent even in populations not traditionally exposed to the Tundra climate. South India is a good case in point. The one plausible reason I can think about is that these communities, by the nature of their climatic and working conditions tended to be heavy users of carbohydrates and glucose. This would normally be used up quite quickly as one went about the dialy grind. But the rapid development in the way of living - a clear sedation of working atmosphere means that the bpdy does not do its share of work in removing the excess sugar from the system. and hence the problem of diabetes.

Additionally, all symptoms of diabetes point to a response of the body towards freezing. The body starts removing excess water through urination, the concentration of sugar increases in the blood. This is intriguing as the body apparently starts acting in a freeze response mode. Is it a case of the body's radar malfunctioning or just something else.