Knowing Your BMI Helps in Tracking Your Health

Monday, November 29th, 2010 at 10:23 PM

BMI stands for Body Mass Index and is calculated using your height and weight, a screening tool to identify weight problems. BMI is a fairly reliable indicator of body fat for most adults, with the exception of athletes and the elderly.

The formula used is: [weight in pounds ÷ ( height in inches ) x ( height in inches)] x 703. An easier way to calculate is to go to an online calculator such as The National Heart, Lung and Blood Institute at: nhlbisupport.com/bmi/.

There are four categories to interpret BMI for adults 20 years and older:

· Underweight = less than 18.5

· Normal weight = 18.5 24.9

· Overweight = 25 29.9

· Obesity = BMI of 30 or greater

Individuals with very low or very high BMIs tend to have the greatest health risks. A BMI in the “normal weight” category indicates a reduced risk of serious health conditions. According to the Centers for Disease Control, overweight and obese individuals are at increased risk for many diseases, including high blood pressure, heart disease, stroke, diabetes, sleep apnea and respiratory problems.

Another easy tool to assess your health risk associated with weight is simply by measuring your waist circumference. This is because abdominal fat is a predictor for obesity-related diseases, the same chronic diseases associated with a high BMI. This risk goes up with a waist size that is greater than 35 inches for women or greater than 40 inches for men.

To correctly measure your waist, stand and place a tape measure around your middle, level with your navel. Measure your waist just after you breathe out. Make sure the tape measure is not too tight and is parallel with the floor.

For children and teens, age and gender factor into the interpretation of BMI. This is because body fat changes with growth and differs between boys and girls. For information on BMI charts for children go to the University of Florida publication, “Raising Healthy Children: BMI Charts” at edis.ifas.ufl.edu/pdffiles/FY/FY119300.pdf.

BMI is an easy way to estimate body fat, but it is only one of many factors that you and your doctor should use in evaluating your health status.

Jill Taufer is extension agent for family and consumer sciences at the Volusia County Extension Service, University of Florida. For information, contact the office, 386-257-6012. The extension service is at 3100 E. New York Ave., DeLand.