Diabetes patients of normal weight are twice as likely to die as those who are overweight

Don't see why the obesity findings re Type II diabetes are paradoxical at all. Type II results from genetic insulin resistance. Insulin resistance most often results in high levels of insulin in order to overcome the resistance, and insulin promotes weight gain--thus the correlation. Those type IIs who do not respond to resistance by producing more insulin don't gain weight, but less insulin means far poorer sugar control. High insulin levels are harmful, but uncontrolled blood sugars are far worse.

http://www.nytimes.com/2012/09/18/health/research/more-data-suggests-fitness-matters-more-than-weight.html

In research conducted to answer that question, Dr. Carnethon discovered something even more puzzling: Diabetes patients of normal weight are twice as likely to die as those who are overweight or obese. That finding makes diabetes the latest example of a medical phenomenon that mystifies scientists. They call it the obesity paradox.

In study after study, overweight and moderately obese patients with certain chronic diseases often live longer and fare better than normal-weight patients with the same ailments. The accumulation of evidence is inspiring some experts to re-examine long-held assumptions about the association between body fat and disease.