By Emme Tran | Copy Editor
Nearly 200 years after body mass index (B.M.I.) was created, the deeply flawed metric is still commonly used in health offices to measure body constitution and obesity in individuals. However, not only is B.M.I. inaccurate towards measuring levels of body fat, but it also contributes to the reliance on weight in health care.
B.M.I. is calculated by taking a person’s weight in kilograms divided by their height in meters squared. According to The Washington Post, the metric was created in the 1830s by mathematician Lambert Adolphe Jacques Quetelet and was restudied by physiologist Ancel Keys in 1972, who coined the term, “body mass index.”After its reintroduction to the health system, B.M.I. began to be frequently used in health checks and by the National Heart, Lung, and Blood Institute to diagnose obesity.
Despite the metric’s longevity in the health industry, its original purpose was not to measure an individual’s level of obesity, but to measure “the degree of obesity of the general population to assist the government in allocating resources” rather than assessing individuals, according to NPR.
Moreover, weight is affected by sex, ethnicity, and age, which are factors that B.M.I. does not consider. Quetelet and scientists in the 1970s used data from predominantly white European and American middle-aged men with little to no data on women and people of color.
Female individuals tend to contain a higher level of body fat due to differences in fat distribution, leading to misdiagnosis since B.M.I. cannot distinguish body fat from muscle or bone, according to Harvard’s School of Public Health. Additionally, the World Health Organization specified a separate B.M.I. for Asian patients due to data showing that Asian patients with a lower B.M.I. have a higher risk for cardiovascular diseases compared to caucasian patients. However, there are no specific adjustments for Hispanic and Black patients, who have a higher risk with a higher B.M.I..
Some health offices also use B.M.I. to incorrectly predict the health of children, pregnant people, and people with high muscle mass. According to nytimes.com, a 2016 study on 40,000 adults in the United States showed that approximately half of the participants classified as overweight while a fourth was actually metabolically healthy. Half of all public schools in the U.S. also continue to measure B.M.I. scores as a part of physical education requirements even though measuring the weights of children for grades promotes body shaming and the negative perception of weight in adolescents.
Rather than relying on weight and body size to directly predict health, modern science has evolved to use more complex, specific measurements of health to diagnose all patients for specific diseases. Linking weight directly to unhealthy eating habits or future health problems can cause physicians to ignore more problematic or prevalent causes of disease. Patients must be assessed more closely through methods such as blood tests to communicate the possibility of acquiring a cardiovascular disease and not something as general as weight.
This metric has been utilized in the health industry for several centuries, but continuously fails to assimilate with diverse populations and the changing outlook on body weight. Healthcare constantly improves in order to treat all individuals, and B.M.I. should as well.