Body mass index (BMI) is a common metric used in health-care institutions to determine patient health.
It has been frequently criticised for oversimplifying what being healthy actually entails, while being used for decades as the standard assessment for health based on body size.
In fact, many people argue that BMI should not be utilised in medical or fitness contexts since it is antiquated and incorrect.
Body mass index is referred to as “BMI”.
A Belgian mathematician by the name of Lambert Adolphe Jacques Quetelet created the BMI in 1832.
According to a research titled “Physiology, Body Mass Index”, written by Asia Zierle-Ghosh et al, he created the BMI scale to swiftly evaluate the degree of overweight and obesity in a specific population to assist governments in deciding where to invest health and financial resources.
Interestingly, Quetelet claimed that BMI was better at capturing the general health of a group than using it to investigate a single individual. Even so, it's frequently used to gauge people's health.
According to Asia Zierle-Ghosh et al., the BMI scale is based on a mathematical formula that calculates a person's “healthy” weight by dividing their weight in kilograms by their height in metres squared.
BMI = weight (kg) / height (m2)
In order to assess if you fall within the range of “normal” weight, your BMI is computed and then compared to the BMI scale.
If you don’t fit the definition of “normal” weight, a health-care expert could advise making modifications to your health and way of life.
This BMI scale has been used by certain nations to more accurately reflect the size and height of their respective populaces.
For instance, a 2014 study titled “Using acceptable body mass index cut points for overweight and obesity among Asian Americans” revealed that Asian men and women had a greater risk of heart disease than non-Asians at lower BMIs.
Despite the fact that this can offer a healthcare practitioner a quick overview of a person's health based on weight, it ignores other aspects of a person's health, including age, sex, race, genetics, fat mass, muscle mass, and bone density.
The majority of research demonstrate that a person's risk of chronic illness and early mortality does rise with a BMI lower than 18.5 (“underweight”) or of 30.0 or above (“obesity”), despite concerns that BMI doesn't precisely indicate if they are in good health.
A 2017 retrospective research of 103,218 fatalities, for instance, showed that those with a BMI of 30.0 or above (referred to as “obesity”) had a 1.5–2.7-fold higher chance of dying following a 30-year follow-up.
Another research with 16 868 persons found that those with a "obese" BMI had a 20% higher chance of dying from any cause and heart disease than those with a "normal" BMI.
Additionally, the researchers discovered that those with "underweight" BMI and “severely obese” or “very obese” BMI died on average 6.7 years and 3.7 years sooner than people with “normal” BMI.
According to other research, a BMI above 30.0 considerably raises the chance of developing chronic conditions such type 2 diabetes, heart disease, breathing problems, renal illness, non-alcoholic fatty liver disease, and mobility problems.
In addition, a 5–10% drop in BMI has been linked to a lower incidence of metabolic syndrome, heart disease, and type 2 diabetes.
Many health practitioners can use BMI as a broad indicator of a person's risk because the majority of studies indicates that obese persons have an elevated chance of developing chronic diseases. But it shouldn't be the only diagnostic instrument employed.
Drawbacks of BMI
There are many problems with the use of BMI, despite data linking low (below 18.5) and high (30 or above) BMI with elevated health risks.
Ignores additional health concerns
Without taking into account a person's age, sex, genetics, lifestyle, medical history, or other considerations, BMI just provides a "yes" or "no" answer as to whether they are of "normal" weight.
By ignoring other vital health indicators like cholesterol, blood sugar, heart rate, blood pressure, and inflammatory levels, such as BMI, one may exaggerate or underestimate their genuine health.
In addition, BMI employs the same formula for both sexes despite the fact that men and women have different body compositions, with males having more muscle mass and less fat mass than women.
Additionally, a person's body fat mass normally rises and their muscle mass gradually reduces as they age. Numerous studies have demonstrated that an older adult's BMI of 23.0-29.9 can be protective against illness and early mortality.
A person's mental health and complex social issues like money, access to inexpensive and nutritious food, food skills and knowledge, and housing conditions are all ignored when a person's health is only determined by their BMI.
Considers all weight to be equal
Despite weighing the same as one kilogramme of fat, muscle is denser and occupies less space. As a result, someone who is extremely slim but has a lot of muscle may weigh more than average.
For instance, a person who weighs 97 kg and is 175 cm tall has a BMI of 29.5 and is considered to be "overweight."
The appearance of two persons who are the same height and weight might vary greatly. One can be a bodybuilder with a lot of muscle, whilst the other might have more fat.
If BMI is the only factor taken into account, it is quite easy to mistakenly label someone as "overweight" or "obese" despite their low fat mass. Therefore, in addition to a person's weight, it's necessary to take their bone, muscle, and fat mass into account.
It's critical that all medical practitioners go beyond BMI to provide patient-centred recommendations because major health choices, such surgical procedures and weight reduction therapies, are focused on BMI and weight.
Body mass index (BMI) is a highly debatable health assessment technique used to determine a person's risk for ill health and body fat.
According to most studies, as BMI rises over the "normal" level, there is an increased chance of developing a chronic illness. Additionally, a low BMI (below 18.5) has been associated with negative health effects.
However, BMI does not take into account other factors that may affect health, including age, sex, fat mass, muscle mass, race, genetics, and medical history. Furthermore, it has been demonstrated that using it as the only predictor of health increases weight bias and health disparities.
BMI is a good place to start, but it shouldn’t be the primary indicator of your health.