Body Mass Index Bmi

By Author: Sulamita Berrezi
Total Articles: 115
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Determined by the indirect calculation of weight in kilograms to the square of height in meters (kg/m2), BMI is a simple and convenient proxy measure for excess adiposity in clinical settings. Many health-related indices, such as mortality risk, heart disease, high blood pressure, and diabetes, have a graded and continuous correlation with BMI. BMI is highly correlated with the precise DEXA method of fat assessment and is thus the universal acceptance as the standard index for the deinition of overweight and obesity. hree methods are used to determine BMI: the calculation of the individual's weight divided by the height in meters squared, the use of several Web-based computation sites, or comparison with published reference tables that plot BMI as height and weight intersect. In adults, regardless of sex or age, one set of BMI values is used to assess adiposity and health risk. Based on classiication by the National Heart Lung and Blood Institute of the National Institutes of Health (NIH), a BMI under 25 is normal, 25-29.9 is overweight, and a BMI of 30 and above is obese. BMI is particularly useful for large population surveys ...
... and for screening purposes; however, it may not always categorize individual risk well. Although BMI represents the degree of body fat, it does not distinguish between excess weight due to fat mass and nonfat mass such as muscle, edema, or bone. For example body builders have a low percentage of body fat, but their BMI may be in the overweight range because of their large lean muscle mass. Individuals with higher fat mass may be classiied as normal BMI despite having a low bone density or muscle mass. Another limitation of BMI is that the relationship to body fatness for those of diferent gender, age, and ethnicity has not been irmly established. In a family study of 665 African American and Caucasian men and women over the age of 17, the relationship of BMI and fat mass was dependent on gender and age, particularly at lower BMI levels. For women, race was also a factor.For children and adolescents, there is controversy regarding the deinition of normal BMI values due to concerns about possible interference with normal growth, self-esteem, and the desire to promote the development of healthy food behaviors and habits. During childhood, BMI changes with growth and development.here are several periods in which sex, growth, and maturation patterns afect muscular gains and account for BMI variation, rather than adiposity. hus, several authorities have developed child BMI levels including the International Obesity Task Force, the British Child Growth Foundation, and the U.S. Centers for Disease Control and Prevention (CDC). In the United States, the CDC charts are based primarily on data collected during national health examination surveys conducted by the National Center for Health Statistics between 1963 and 1994, and as such, are not skewed by recent increases in the prevalence of overweight children. A BMI equal or greater than CDC's 95th percentile for age and gender has a sensitivity of 49 percent and speciicity of 90 percent in identifying children with three or more risk factors for cardiovascular disease.