BMI: A Screening Tool?
Recruitment challenges are on the rise and the more restrictions imposed in the process the more talents are lost. We need to examine all currently implemented recruitment tools to improve the process, including the Body Mass Index (BMI) restriction.
Obesity is an epidemic affecting different age groups, genders and countries all over the globe. Since 1980 obesity levels have been on the rise and the number of obese people has more than doubled (1). In an effort to simplify, standardize and consequently compare obesity levels and trends worldwide a simple measure called BMI, used to evaluate weight status of individuals, was adopted (2).
BMI is calculated by dividing a person’s weight in kilograms by the square of height in meters – this is compared to standardised cut-off points to evaluate whether a person is underweight, has normal weight, is overweight or is obese (2,3). Though BMI reflects the percentage of fat yet it does not measure it in a direct manner (3). The association between BMI and amount of body fat is strong, yet there are conditions when an individual with a high BMI might have high levels of lean body mass like muscles or bones such as the case in individuals who perform regular athletic training or athletes (3). BMI levels can differ in terms of sex and age where women and older individuals are more likely to have more fat than men and younger individuals respectively (3).
Also, BMI levels can differ among individuals from different ethnicities (3). Studies have shown that at a given BMI Asians tend to have more body fat than Caucasians (4,5) whereas individuals of African descent tend to have less body fat than Caucasians (6).
Seemingly, BMI fails to measure central adiposity. A review of several studies has revealed an association between abdominal or central obesity (which is not reflected by BMI) and health risks (7). They also showed that measures like waist to height ratio is more accurate than BMI in detecting risk factors such as cardiovascular diseases, hypertension and diabetes (7), this suggests that BMI should only be used as a screening tool rather than to diagnose individuals as having excess fat or as unhealthy where further accurate tests are needed to confirm such a diagnosis (3).
Accordingly, we might want to look for a more scientific approach than using BMI as a recruitment screening tool. Those who have BMI levels beyond a set value might not yield accurate assessments given the shortcomings of the BMI measure and accordingly increases the possibility of losing a good candidate who may, in fact, be healthy.
- World Health Organization. Fact sheet: Obesity and overweight. http://www.who.int/mediacentre/factsheets/fs311/en/. Updated 2016. Accessed September/10, 2016.
- World Health Organization. Global database on body mass index: About the BMI database. http://apps.who.int/bmi/index.jsp?introPage=intro.html. Updated 2016. Accessed September/10, 2016.
- Center for Disease Control and Prevention. Healthy weight. https://www.cdc.gov/healthyweight/assessing/bmi/adult_bmi/. Updated 2015. Accessed September/10, 2016.
- Liu A, Byrne NM, Kagawa M, et al. Ethnic differences in the relationship between body mass index and percentage body fat among Asian children from different backgrounds. Br J Nutr. 2011;106(9):1390-1397. doi: 10.1017/S0007114511001681.
- Deurenberg-Yap M, Deurenberg P. Is a re-evaluation of WHO body mass index cut-off values needed? The case of Asians in Singapore. Nutrition reviews. 2003 May 1;61(suppl 5):S80-7.
- Wagner D, Heyward V. Measures of body composition in blacks and whites: A comparative review. Am J Clin Nutr. 2000;71(6):1392-1402.
- Ashwell M, Gunn P, Gibson S. Waist?to?height ratio is a better screening tool than waist circumference and BMI for adult cardiometabolic risk factors: Systematic review and meta?analysis. Obesity Reviews. 2012;13(3):275-286. doi: 10.1111/j.1467-789X.2011.00952.x.