Sign in

Is the Body Mass Index (BMI) a Reliable Health Indicator?

sajid khan
Is the Body Mass Index (BMI) a Reliable Health Indicator?

Is the Body Mass Index (BMI) a Reliable Health Indicator?

There are many individuals who have experienced this: You visit the doctor, get your blood pressure, height, and weight taken, and then the doctor breaks the bad news that your BMI is too high and that you need to lose weight.

In the United States, body mass index, sometimes known as BMI Calculator" target="_blank" style="color: rgb(0, 0, 0); background-color: transparent;">BMI, is frequently used to determine an individual's weight. According to the Centers for Disease Control and Prevention (CDC), 42.4 percent of American people aged 20 and over are obese, according to the federal government's measurement of the nation's obesity statistics.

Adults may calculate their BMI by multiplying their height in square inches by 703, then subtracting their body weight in pounds from that result. If arithmetic isn't your thing, use the Advance BMI calculator instead.

According to the CDC, this is what your number means:

BMI under 18.5 indicates underweight.

Normal ranges are from 18.5 to 24.9.

Overweight ranges from 25 to 29.9.

Additionally, obesity is present in those above the age of 30.

It's true that this formula is convoluted and somewhat arbitrary. And a lot of professionals now doubt the veracity of the BMI.

BMI is far from ideal, and as time has gone on, more and more science has come to light that exposes the shortcomings of this methodology.

Before exploring what those flaws actually are, it's critical to comprehend the history of BMI as well as what your BMI suggests about your health. This will help you realize why you shouldn't immediately go into panic mode if your doctor tells you that your number is too high.

The American History of BMI

Researchers, medical experts, the government, and insurance companies first developed BMI because they wanted an easy measure to monitor health risk among Americans. The phrase "body mass index" was first used by researcher Ancel Keys in his 1972 work "Indices of Relative Weight and Obesity." According to one report, that is. He examined the adiposity-body density and subcutaneous fat thickness, two indicators of body weight, in 7,400 males from five European nations for the research. Adolphe Quetelet created a weight-to-height index in 1832, known as the Quetelet index. Keys developed the body mass index as a simple way to calculate body weight in proportion to height.

Epidemiologists all across the world started utilizing Keys' body mass index technique as a tool to track disease risk factors in the general population as individuals got increasingly overweight and the health problems associated with being overweight became more obvious.

The National Institutes of Health (NIH) began defining obesity in the United States using BMI in 1985. The standards were initially more restrictive, but by 1998, the NIH began adopting the above simpler categories that now include all ages, all sexes, and all cultures. Research indicates that in 1998, the NIH established such standard.

What Your BMI May Tell About Your Health and How Experts Use It

Your healthcare might be linked to that one number. If you have a high BMI, your doctor might feel compelled to do more health exams, prescribe certain medications, and set up more follow-up appointments to check on your weight. Your healthcare expenses are impacted by your BMI in this way.

High BMI and Chronic Disease

After all, evidence from studies shows that BMI and illness risk are tightly related. The National Institute of Diabetes and Digestive and Kidney Diseases reports that those who are deemed overweight or obese are more likely to develop chronic illnesses including heart disease, type 2 diabetes, stroke, and even cancer.

High BMI and COVID-19

In addition, researchers found in a study of British people published in August 2020 in PNAS that the probability of hospitalization for COVID-19 rose along with BMI. According to the study, the elevated risk may have resulted from poor lipid and glucose metabolism.

According to a different research published in the August 2020 issue of Obesity Reviews, those who are fat have a 48 percent higher chance of dying from an illness than those who are not obese.

The final word? The standard definition of BMI is used to assess health risk. However, it cannot reveal a person's health-related behaviours. BMI does not reveal a person's diet, exercise habits, sleep patterns, or stress levels—all factors that have an impact on health. Additionally, healthy behaviors can greatly safeguard you regardless of your weight. For instance, obese people who followed the Mediterranean diet did not have a greater overall mortality risk that is often linked with a higher BMI, according to population-based research on middle-aged and older men and women published in PLOS Medicine in September 2020. 

However, people with higher BMIs did have a greater chance of passing away from heart disease. The authors of the study noted that some (but not all) of the health issues linked to being overweight can be mitigated by lifestyle choices.

Why BMI Isn't the Best Way to Detect Obesity and Overweight

BMI has flaws while being widely used. The scale has drawn more attention as more and more people fall into its high-risk categories of being overweight or obese. According to Kim Larson, RDN, a health and wellness consultant at Total Health in Woodinville, Washington, "Body mass index doesn't show the difference between muscle and fat, so it doesn't always accurately predict when weight could lead to health problems."

Those for Whom BMI May Not Be Accurate

If you fall into one of the following categories, your BMI may not always be the greatest indicator of your body fat and general health.

  1. Asian people: East Asians According to study, Asian people may experience elevated health risks before their height and weight computation indicates that they are overweight (BMI of 25 or more). This means that the BMI scale is not an appropriate assessment for Asian people. Asians are more prone to have abdominal (sometimes known as "visceral") fat, which is particularly harmful, according to the American Heart Association. As a result, the Joslin Diabetes Clinic advises clinicians to utilize a BMI scale with lower BMI cutoff values for Asian patients.
  2. women who are breastfeeding or pregnant According to the CDC, women often have a greater body weight and body fat percentage while they are breastfeeding or pregnant. According to the CDC, this is done so they can feed the infant; it is not a sign of long-term health hazards.
  3. Athletes According to a research, those who are exceedingly active have larger bones and more lean mass (think muscle), which leads to greater body weights and BMIs. However, a different study found that lean muscle mass can boost metabolism and protect against diseases including type 2 diabetes and heart disease. Consequently, a high BMI athlete may not always be harmful.
  4. not pregnant women Women typically have a larger amount of body fat than males, according to study.
  5. individuals above 65 People older than 65 have a greater relative health risk when their BMI is less than 23. The lowest risk of death within this age group is associated with a BMI of 27, according one report in a prior meta-analysis. Although the cause is not entirely understood, it most likely has several factors. In comparison to people who have a lower BMI, persons with a higher BMI often carry more pounds of muscle, which has a protective effect on general functioning, fall risk, and immunity.
  6. Healthcare professionals are cautioned by the CDC not to assess BMI with the goal of using it as a diagnostic tool. The American College of Obstetricians and Gynecologists notes that despite this, there is an ICD-10 (diagnosis code) for overweight and obesity, indicating that some people may still have these conditions.

  7. The organization also makes the point that extra body fat, which may be a better sign of your health status, is not measured by BMI. Consider it this way: When you walk on the scale, the number shown (which is used to determine your BMI) does not take into consideration the composition of your body weight or the distribution of that weight throughout your body.

The BMI Scale: Is It Racist?

The racial foundations of BMI are becoming more well known or under the spotlight. How can everyone else, especially women who belong to the Black, Indigenous, and People of Color (BIPOC) group, use this scale since it was created after studying white European men? After all, this was a scale that was built after seeing them.

According to Sara Bleich, PhD, a public health policy professor at the Harvard T.H. Chan School of Public Health in Boston, it is unquestionably true that the BMI was evaluated and verified in a white male population.

However, Dr. Bleich argues that because of how BMI has changed over time, it is still valuable as a tool. We would need to be concerned if BMI were solely used in its original form, according to Bleich. "So many various studies have examined the danger of excessive BMI in several groups, and they all consistently demonstrate that having a higher BMI is unhealthy. The fact that being overweight is statistically common in this nation is a significant difficulty since, as she points out, carrying extra weight raises your chance of developing chronic illnesses every day, regardless of your race.

It's also crucial to draw attention to the stigmatization that occurs from having a higher BMI than average. Because you fear being criticized, obese people sometimes delay seeking treatment. By the time you're seen, your health issues have worsened, and it becomes this terrible cycle, says Bleich. Most doctors are not educated or trained to deal with obesity, thus they are more likely to give patients useless advice ("Exercise and eat healthy!")

Health problems may be exacerbated by racism itself. Several health inequalities, notably a higher BMI among Black individuals, are linked to structural racism, according to a research published in the October 2020 issue of the American Journal of Preventive Medicine. The authors define structural racism as institutional policies and practices that lead to unfair treatment of members of a specific racial group. This connection first became apparent ten years ago, when studies showed that while obesity rates were rising, it was not happening uniformly across the board. White males with education were growing fat at the slowest pace, while Black women without education were becoming obese at the highest rate. 

BMI: How Accurate Is It?

The CDC describes the link between BMI and body fatness as "fairly strong." However, a few studies have examined the accuracy of BMI, including how frequently the number correctly detects obesity and when it does not.

Based on blood pressure readings, metabolic lab results, such as HDL ("good") and LDL ("bad") cholesterol, glucose, triglycerides, and C-reactive protein, one study with more than 40,000 participants across all population groups found that more than 30% of people in the normal BMI category are cardio-metabolically unhealthy. Additionally, according to their health indicators, 29% of those who were obese and close to 50% of those who were overweight were in good health. According to these additional criteria, up to 74 million people who are categorized as unwell based on their BMI are actually healthy, according to the study's authors.

One more PLoS According to one study, a quarter of men and almost half of women who were considered obese based on their body fat percentage did not meet the criteria for that classification based on their BMI. Using biomarkers and dual-energy X-ray absorptiometry, it was shown that 39% of study participants were obese but were not considered such by BMI alone.

Occasionally, inaccurate height reporting is the cause of BMI inaccuracy. A different research found that approximately 15% of individuals overestimated their height while 29% underestimated it.

But despite its shortcomings, BMI is nevertheless regarded as a valuable tool by professionals in the field of obesity. According to Bleich, research generally indicates that when a person's BMI increases, so does their chance of developing various adverse health diseases, such as type 2 diabetes, heart conditions, and hypertension. That provides strong support for the idea that as BMI rises, health risks do as well.

If BMI Has Problems, Why Do Doctors Still Use It?

The CDC notes that BMI has some value. It is a quick, low-cost, and non-invasive method of determining body weight. Because it is simple to compute and has been frequently applied, statisticians may easily quantify obesity in broad populations using this method.

Health professionals should be aware of the drawbacks and restrictions of BMI. Even if physicians check someone's BMI at routine visits, it shouldn't be the primary criteria used to determine if they are overweight or obese.

BMI alternatives

The majority of medical specialists agree that there should be numerous parameters used to estimate health risk. Age, gender, medical history, any unusual blood laboratory findings, and family history are a few of them.

Y2Calculate.com" target="_blank">BMI measurement are ubiquitous among medical professionals and the general public, but is there a more accurate way to determine your health? Here are some potential candidates.

Waist Measurement

Your waist circumference should be less than 40 inches for males and less than 35 inches for women, according to the National Heart, Lung, and Blood Institute.

ratio of waist to height

According to study, having a waist-to-height ratio more than 0.5 may increase your chance of developing diabetes and heart disease.

Waist-to-Hip Ratio

According to the World Health Organization (WHO), high risk is defined as a ratio of 0.85 or higher for women and 0.9 or higher for males. By calculating the size of your waist and dividing it by the circumference of your hips, you may get your waist-to-hip ratio.

End Note 

The BMI is just one screening measure, and it shouldn't be used in isolation to determine someone's health risk. Even if your BMI is very high, you may not necessarily be in bad health.

For a more accurate picture of your current and future health, all aspects, including your personal and family health history as well as more precise body measurements paired with the factors taken into consideration in BMI, must be taken into account.

<a href="https://y2calculate.com/prize-money-split-calculator/" target="_blank" title="Calculate Prize Money Split" rel="follow">Prize Money Split Calculator</a>

sajid khan
Zupyak is the world’s largest content marketing community, with over 400 000 members and 3 million articles. Explore and get your content discovered.
Read more