Fat Fat Free Mass Should We Measure in

Fat & Fat Free Mass Should We Measure in MESA II?

Scientific Rationale The effects of obesity are of major medical importance. Currently our only measure of obesity is BMI doesn’t fully account for differences in body composition that are unrelated to fat mass. – It may overestimate body fat in athletes and others who have a muscular build. – It may underestimate body fat in older persons and others who have lost muscle mass. – BMI is highly correlated to weight (r=0. 8315).

Example of two individuals classified as obese based on BMI Ladamlian Tomlinson, running back for San Diego Chargers football team has a BMI of 33. 6 , based on a height = 5’ 8’’ and weight = 221 lbs. A man with similar BMI

Use of Biolectrical Impedance (BIA) to Measure Fat and Fat Free Mass BIA has been well validated. Reference results available from NHANES III for whites, non-Hispanic blacks, and Hispanics (Body composition estimates ( from NHANES III bioelectrical impedance data. International Journal of Obesity (2002) 26, 1596 – 1611. Total body water is also measured.

Practical Aspects Choice of device – Tanita – Valhalla – Impedimed Tanita and Valhalla devices include a scale and take only a minute or two more than just weighing the person. The Impedimed device requires attaching two electrodes.

Recommendation Valhalla device offers multiple advantages – Customized Report Available – No Disrobing - Keep Those Shoes On – Better than 0. 5% repeatability – Correlates with Hydrostatic Weighing to within >99% – Accurate for athletes, bodybuilders, elderly and the obese – Device used by NHANES – Cost - $2, 895 per unit Fund from main study budget

Valhalla BIA Device

Valhalla Report