Is BMI Accurate?
BMI is broadly used from the medical community as a screening tool that estimates weight status as well as the related possible risks of diseases for someone’s health.
Despite that, there are cases where quite naturally, one question arises into people’s heads: Is BMI accurate?
A high BMI usually(but not always) is an indicator of more body fatness, and having a low BMI can be a marker of small body fatness.
The high amounts of body fat are a potential cause of weight-related health complications or being underweight can also put you at risk of health problems.
And at all, BMI is an easy way to describe a person’s weight category, but it is not enough to assess an individual health risk without digging further.
It provides a piece of information, though by itself does not indicate the presence or absence of health.
Therefore, keep in mind that BMI is widely applied but as a screening tool, not as a diagnostic one.
It means that are necessary further health assessments to decide what is someone’s health status and what are the eventual specif risks are threatening his health.
Where does BMI Go Wrong?
The personal BMI result is found when the person’s weight in kilograms is divided by height in meters squared.
But it appears that there is a “trap” because calculating in that way, BMI may overestimate thinness in the short people and fatness in tall people. Why is this happen?
Nick Trefethen, who is Professor of Numerical Analysis at Oxford University’s Mathematical Institute, in a report to The Economist, revealed that BMI leads to misinformation and confusion.
Professor Trefethen, admits that the BMI weight/height2 expression in some cases divides the weight by too much for small people and too little in tall individuals. What does this mean?
BMI does not consider the body shape of those persons, which misleads a tall person to believe that he is fatter than he is, or the short one to assume that it is thinner while it isn’t.
What is the conclusion?
BMI does not consider the body shape of those persons, which misleads a tall person to believe that he is fatter than he is, or the short one to assume that it is thinner while it isn’t.
Is BMI Accurate and What It Misses Showing Us?
BMI does not consider things like muscle mass, type of body shape, or where your body stores fat
The medical community considered that BMI indicates the amount of body fat a person has based on their height and weight. In that way, people are categorized based relatively on their size.
A BMI reading under 18.5 it shows that you are underweight. If BMI is from 18.5 to 24.9, you’re qualified healthy, while a BMI of 30 or higher is considered as overweight.
Research shows that there are cases where people that have obese BMI are metabolically healthy, and same time there are people with normal BMI that can be metabolically unhealthy.
For example, because muscles are much denser than the fats are, very muscular people, such as bodybuilders, sumo fighters, and many professional athletes, are with BMI over 30 and more.
Those like the wrestler Steve Austin, at the peak of his career, he has weighed 114 kg (252 lbs) and 6ft 2ins tall. And his BMI figure has been 32.4, which would put him in the obese category.
Muscle weighs more than fat; thus, BMI will surely class muscly and athletic people as fatter than they are
Although, they are classified as “obese,” actually they are in functional health status and perfect health condition.
That calculation is probably right for that one sedentary on the couch eating tasty chips watching TV shows, but not for the athlete.
Another typical example in our society is when a slim person is with a “normal or healthy” BMI (18.5 – 24.9) but at the same time has EXESS weight but only around his waist in the form of more belly fat.
In this case, although that being with healthy BMI, the fat belly directly exposes the person’s health to a high risk of complications like cardiovascular disease and Type 2 Diabetes.
Those are cases where BMI meaning is compromised, and in other words, inaccurate and misleading.
Authoritative organizations as Centers for Disease Control and Prevention (CDC), as well as The National Institutes of Health (NIH), still promote BMI.
They consider that BMI is a reliable indicator of body fatness for most people.
Even so, when it comes to analyzing how weight affects health at the population level, it’s still a useful first step.
Going Beyond BMI
One crucial information that BMI cannot determine is the type and location of fat on your body. Because it turns out that having excess fat is a critical factor in your overall health
If you have fat on the butt, legs, or back, this has minimal harmful impact compared with fat located at your midsection (the BMI makes no difference between the two).
The reason the abdominal fat to be so dangerous is in part to its proximity to the intestinal organs.
The fat that is in your butt and other areas listed above are mostly so-called subcutaneous fat, whereas the fat around your belly area is mostly so-called visceral fat.
Visceral fat is that which disrupting your metabolism and ends up causing more inflammation, leading accumulation of more fat in the belly region
Why belly fat is so dangerous
In the normal healthy state, the body tissues will use oxygen to burn off any excess fat.
When you gain weight, and especially as fat tissues around your waist, this causes your fat cells to grow becomes larger, suppressing the oxygen circulation.
The lack of oxidation promotes more body inflammation and, in turn, the accumulation of more and more fat.
Dangerous of belly fat
There is so much study confirming the devastating effects that sustained belly fat can cause on your body.
Having an “apple-shaped” body frame is also heavily associated with more inflammatory diseases.
Carrying excess visceral fat can result in increased insulin resistance, which may cause glucose intolerance and type 2 diabetes. Other risks that exist include heart disease, heart attacks, stroke, but also breast and colorectal cancer and Alzheimer’s disease.
On the other hand, those with a “pear-shaped” body who tend to store their fat on their hips are at lower risk of heart disease and diabetes.
That’s why medical providers will relying upon to measure not only BMI but also the waist circumference to determine more precisely the level of risks of these diseases.
By using this method, men’s waists should be no more than 102 centimeters (40 inches), and women should be no more than 88 centimeters (or 35 inches).
Final thoughts
Is BMI accurate? To answer the question, we have revealed that at its core, BMI is just a rough evaluation – a point from which are needed further analysis and examinations for making the precise conclusions.
There are plenty of people out there with a high or low BMI who are also very healthy and, conversely, many people who have a normal BMI who are pretty unhealthy.
For instance, a person with a perfectly healthy BMI but leaded sedentary life, heavy smoker, and no good family history (health predisposition) of the cardiovascular disorder are at higher risk of early death.
Unlike another more genetically lucky person who has a higher BMI but is also a physically good and non-smoker. Right?
So, I think it’s an excellent thing to know your BMI but also to consider its limitations.
