are you fat? You don't need a scale or a meter, just a string to know

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Obesity rates are increasing globally day by day, and here the question arises: “Is the method of assessing obesity by calculating the body mass index (BMI) really accurate?”

The answer is no, what is most important is measuring the waist to height ratio.

Body mass index (also known as body mass index) is a number calculated using a person's height and weight, and is used to evaluate whether most people are overweight or underweight.

BMI does not measure the amount or percentage of fat in the body, but researchers have found that it is usually related to the percentage of fat in the body, and therefore it is an indicator of the amount of fat a person has, and it is also a means of assessing health risks using the person’s weight and height.

The body mass index is calculated by dividing a person's weight in kilograms by the square of his height in metres. For example, if the person's height is 170 centimeters and his weight is 75 kilograms, then 170 centimeters are converted to the unit of meters and it becomes 1.7, then the weight is divided by its square: 75/2 (1.7) and the result is In this case 25.95.

If the body mass index is less than 18.5, the person is classified as underweight.

If the body mass index is from 18.5 to 24.9, the weight is classified as normal, but between 25 and 29.9, the person is overweight, and if the body mass index is 30 or more, the person is obese.

According to a report in Times Magazine, the body mass index was not developed by a doctor, but by a Belgian astronomer named Adolphe Quetelet in 1832, to determine “normal” weight based on white European men in the 19th century.

However, this index has been adopted over the years for various guidelines, and in 1995 it was adopted by the World Health Organization as the official standard for weight classification.

Calculating BMI is a quick calculation, but it is crude and can produce misleading results for a variety of reasons.

A medical report - which will be published soon - questions whether body mass index is a reliable measure or whether the method of using it needs to change.

The report of the Lancet Commission on Obesity - a collaboration between leading scientists and doctors from around the world - is scheduled to be published within the coming months.

One of its authors, Naveed Sattar, professor of cardiovascular medicine at the University of Glasgow and chair of the UK government's obesity committee, says the report could change the way we deal with obesity.

BMI defects

The BMI does not take into account racial and gender differences or body composition, including muscle mass.

A fit and muscular athlete may have a BMI that realistically classifies him as overweight, while people with the same BMI may have significantly different levels of body fat.

Also, the BMI does not tell you where fat is distributed in the body, which represents its biggest disadvantage in terms of disease risk.

It's known from studies that carrying fat around your middle is associated with higher rates of type 2 diabetes and cardiovascular disease than body fat carried around your extremities, something the BMI scale fails to examine.

Some people may have a "normal" BMI, but they are still at increased risk for metabolic disease depending on where body fat is distributed and on other factors such as blood pressure and blood fat levels.

Last year, the American Medical Association described BMI as an “imperfect measure” and encouraged doctors not to rely on it as the only way to assess obesity.

The association now suggests that doctors use a variety of different measurements, including waist-to-height ratio and waist circumference.

This follows changes to obesity guidelines in England made by the National Institute for Health and Care Excellence (NICE) in 2021 to recommend that waist-to-height ratio measurements be used alongside BMI calculations in determining someone's risk of developing obesity and associated diseases.

The new report will suggest a step-by-step approach to weight assessment, where only BMI is used as the primary measure.

Hence, Starr says, the guidelines will reinforce the need for doctors to use waist circumference as an additional test to provide better insight into the risk of metabolic and cardiovascular diseases.

"In addition, doctors will suggest certain blood tests and other procedures to check whether excess weight in a specific, at-risk person is leading to measurable problems related to organ and tissue dysfunction," he continues.

This will include tests of your blood pressure, blood lipids, liver and blood sugar level.

It is no longer just a matter of determining whether someone is overweight, but to what extent excess fat is harmful to their health.

“We need to know whether the fats people carry are leaking into the wrong places and determining whether they affect internal organs or not,” says Starr. “This will help determine appropriate prevention and treatment methods for diseases.”

How do you determine if you are fat without a scale?

The answer is you have to check your waist to height ratio.

“Many diseases are caused by the ratio of fat to muscle mass, and the waist-to-height ratio test tells you more about that than the BMI,” says Starr.

For your weight to be normal, your waist circumference must be less than half of your height.

This means that a man who is 1.78 meters tall should have a waist measurement of 35 inches (88.9 cm) or less.

For a woman who is 1.63 meters tall, her waist measurement should be 32 inches (81.3 cm) or less.

You don't even need a tape measure but can use a piece of string to make the assessment, says Dr. Margaret Ashwell, an obesity researcher and honorary fellow of the Nutrition Society.

She says: “Measure your length using the string, then cut it in half and wrap this section around your waist. If half the length of the string does not surround your waist, this is a sign that you are carrying a lot of belly fat.”

While measuring your waist circumference, you should not hold yourself back, but rather breathe normally.

Measuring your waist circumference tells you how much fat you carry around your middle.

This belly fat consists of subcutaneous or visible fat and hidden visceral fat that sits around the organs and is particularly worrisome because it releases proteins that cause a type of inflammation that can lead to type 2 diabetes and high blood pressure.

Where do you place the tape to measure your waist?

Locate and place the tape between the bottom of your ribs and the top of your hip bones, usually just above your navel.

Obesity is linked to health problems from type 2 diabetes to high blood pressure, joint problems and high cholesterol.

That's why it's important to combat it.

Source: Al Jazeera + Agencies + Times