Two seasons into his San Francisco 49ers incarnation, former Stanford coach Jim Harbaugh has yet to draft one of his former Cardinal players. Harbaugh owned the 34th pick and could have selected 65, 249pound tight end/Hback Zach Ertz to replace the freeagent departure of Delanie Walker to Tennessee. Instead, Harbaugh, who recruited Ertz, traded out of the 34th spot with the Titans, who moved up to select receiver Justin Hunter..Carnethon says that the trend is probably driven by a subset of people who are thin yet 'metabolically obese': they have high levels of insulin and triglycerides in their blood, which puts them at a higher risk for developing diabetes and heart disease.All this suggests that BMI is a crude measure for evaluating the health of individuals. Some researchers contend that what really matters is the distribution of fat tissue on the body, with excess abdominal fat being most dangerous; others say that cardiovascular fitness predicts mortality regardless of BMI or