Recently across the United States there has been a wave of legislative propositions to battle the American obesity epidemic. These measures range from regulating the size of sugary drinks to mandating full nutritional disclosure at fast food restaurants. The laws largely use the BMI formula to cite the growing American wasteline. Some opponents of the law challenge the logic behind using the body mass index to measure obesity.
Body Mass Index or more popularly known by its abbreviation BMI, is a calculated number based on a person’s weight and his or her height which provides as an indicator regarding the fatness of one’s body which is useful in determining an individuals’ risk level when it come to certain health problems. One thing to remember when it comes to Body Mass Index is that it is a not an indicator when it comes to overall fat percentage. BMI has been recognized and used by the World Health Organization as a method in recording the statistics for obesity statistics. Calculating for BMI is relatively easy as well and does not require any complicated or expensive equipment.
The formula for BMI is defined as mass in terms of Kilograms divided by the square in meters of an individual’s height. Another easy method to indentify one’s BMI number is through the use of BMI charts with standardized weight levels over height. The normal BMI level that can be regarded as healthy or normal according to the World Health Organization is between the numbers 18.5 to 25. Having a BMI below 19 is indicative that an individual is underweight while a BMI number of above 25 is indicative that an individual might be overweight. Above 30 or 35 in some charts are indicative that an individual is obese or morbidly obese. An individual who is either under or over the “healthy” BMI level is said to have an increased risk in certain diseases and conditions particularly lifestyle diseases like cardiovascular disorders and Diabetes Mellitus.
Even though the World Health Organization have given BMI values, there are many variations when it comes to BMI. In countries like Japan, Singapore and the United States, the BMI values vary to a degree. In 1998, the United States revised their BMI calculations and geared it in line with the standard WHO has set. The healthy cut-off limit was set to a BMI of 27.8 and was revised to BMI 25. This considerably led to millions of people falling into the category of underweight when the new standard was implemented. In Japan, the normal cut-off is set at 22.9 as opposed to the 25 set by the World Health Organization.
There are many major limitations when it comes to using BMI For one, the calculations require the overall weight and height of an individual to determine his or her risk level when it comes to certain diseases and if he or she is under the normal level. It does not however pinpoint or provide information when it comes to the distribution of lean mass and fatty tissues. Furthermore among athletes, BMI also proves inaccurate as muscle mass tends to put them above the normal level even though their fat percentage is low. BMI also does not account for an individual’s frame size. Aside from that, different races with their relative average height and body frame also tend to require different cut-off levels.
BMI values for the elderly as well as for children also follow a different formula. Factors like bone density, muscle mass, height and even body frame can all affect one’s standing in the BMI scale. Even though Body Mass Index calculations have limitations it can provide the general population an idea regarding the likelihood or risk level they have with certain health problems and when it is time to mind one’s health.