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Dr. David J. Demko, gerontologist and editor, AgeVenture News Service, Boca Raton, Florida 12-19-07 
What medical science thinks about obesity may be yesterday's news. Obesity, clinically defined as a 20 percent higher than normal for one's age and gender,
may not, in and of itself, be a risk factor to cardiovascular diesease. BMI (Body Mass Index) is a weight-to-height ratio commonly used to gauge obesity.
UT Southwestern University researchers say that a normal BMI is between 18.5 and 25. Someone with a BMI of 40 is considered morbidly obese. Researchers at UT state that the recommended Body Mass Index (BMI) criteria for obesity (bariatric) surgery should be lowered. Lowering the BMI criteria for obesity surgery would help identify a unique group of overweight patients who are at risk to cardiovascular (heart and artery) disease. This group, say the researchers, have "an almost unlimited ability to store excess calories as fat." This unlimited ability to store excess fat prevents changes in plasma metabolites, such as triglycerides and cholesterol, which promote risk for heart disease. The study, appearing in the December 2007 issue of the journal Surgery for Obesity and Related Diseases, is among the first to evaluate the risk-factor relationship between body mass index (BMI) and cardiovascular disease as it relates to bariatric surgery criteria, say the study's authors, Dr. Edward Livingston (UT GI/endocrine surgery), Dr. Nicola Abate (UT Center for Human Nutrition), and Dr. Manisha Chandalia (UT Center for Human Nutrition). The research demonstrates that cardiovascular risk factors do not necessarily worsen with increasing obesity. Bariatric weight-loss surgery is currently recommended for patients with a BMI greater than 40, as well as for patients with a BMI greater than 35 who also suffer from a life-threatening illness, such as non-insulin dependent diabetes, sleep apnea or heart disease. The study findings show that some morbidly obese patients have better cardiovascular disease risk profiles than those who are less obese. In particular, the researchers found that cardiovascular risk factors can be much worse in many individuals with a BMI as low as 30 than they are for some surgical candidates with higher BMIs. Some patients who are not yet extremely (morbidly) obese might be able to reduce their risk to cardiovascular disease by electing to have obesity (bariatric) surgery. It is possible, say the UT researchers, that "very obese patients simply have a greater capacity to store excessive calories in their adipocytes, or fat cells, thereby preventing excessive fat from spilling into the bloodstream, where it contributes to heart disease." The research findings are based on the examination of patient data from the Third National Health and Nutrition Examination Survey database for the presence of known cardiovascular risk factors as a function of obesity. The survey was a cross-sectional study conducted from 1988 to 1994. All 17,234 participants had a BMI greater than 20.
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