A Third of People in Normal Weight Range ‘Are Actually Obese’

Written by Lia Onely on July 27, 2023. Posted in Current News

Body fat percentage is a more reliable indicator of an individual’s general health than body mass index, according to a new study

Researchers at the School of Public Health at Tel Aviv University Faculty of Medicine analyzed the anthropometric data of 3,001 Israeli women and men, 20 to 95 years old, accumulated over several years, along with cardiometabolic blood markers, body mass index (BMI) scores, and dual x-ray absorptiometry (DXA), which measure body composition, including fat content.

The researchers recommend that a body fat percentage index—meaning assessing excess fat—should be the gold standard of measuring obesity, and that clinics in Israel and worldwide should be equipped with suitable devices to measure this.

The paper was published in Frontiers in Nutrition.

The researchers examined a phenomenon called “the paradox of obesity with normal weight,” meaning a higher than normal body fat percentage in normal weight individuals.

About one-third of the participants were found to be within the normal weight range. Of these, 38.5 percent of the women and 26.5 percent of the men were identified as “obese with normal weight,” according to the study.

Obesity was defined as fat mass above 25 percent for men and 35 percent for women in the study.

BMI Versus Body Fat

Body fat percentage is a much more reliable indicator of an individual’s overall health and cardiometabolic risk than BMI, which is widely used in clinics today, the authors concluded.

BMI is calculated as weight divided by height squared.

Matching body fat percentage with blood markers for each of these individuals, the study found a significant correlation between “obesity with normal weight” and high levels of sugar, fat, and cholesterol, major risk factors for a range of cardiometabolic diseases.

Yair Lahav, a doctoral student and clinical and sports nutritionist who co-authored the study, told The Epoch Times that BMI misses a lot.

“There may be a situation where the BMI is normal, but the amount of fat is high,” he said.

A family doctor or a clinical dietitian should tell their patients that although they think they are thin, they may suffer from a phenomenon called “TOFI,” which means thin on the outside, fat on the inside, Mr. Lahav said.

These people often “go under the radar” of the health care providers instead of being sent for follow-up tests and being guided for proper nutrition, physical activity, and a healthy lifestyle, lead study author Yftach Gepner, professor at the School of Public Health of Tel Aviv University, told The Epoch Times.

All these people “start a state of pathology at a stage where we could detect them earlier,” he added.

The results of the study “were surprising,” said Mr. Gepner.

“We knew that the phenomenon of obesity at a normal weight is high in significant percentages, but not to that extent,” he said.

Health in Israel

As of today, 60 percent of Israel’s population is overweight and obese, Mr. Gepner said, adding that the current study shows that the situation is even worse, because when evaluating the fat percentages, 30 percent of those who appear to be of normal weight are actually obese, he said.

A third of the people who are at a normal weight and think they are in great shape “are actually unaware of what is happening inside their bodies,” he said.

The data between the United States and Israel are similar, said Mr. Lahav.

“The definition of obesity is the amount of fat in the body, not our weight,” said Mr. Gepner. “But it is much more convenient for the health care system to check weight and height than to put them on a device that checks electric conductivity.”

Although higher weight is related to morbidity, the percentage of body fat has “a much stronger relationship” with morbidity, he said, adding that a person who is underweight but who has a fat percentage higher than the norm can be at high risk for morbidity.

Five percent of the people who were underweight were found to be obese, he said, adding that even a slim model who eats junk food and doesn’t work out at all is not immune to obesity.

On the other hand, 30 percent of the men and 10 percent of the women in this study were overweight. Their BMI was between 25 and 30, so the result was that most of their weight is composed of muscle mass instead of fat mass.

The BMI index assessment is not “reliable” and “not sensitive enough,” said Mr. Gepner, since it looks only at the body but not what’s inside, and it leads to a “misclassification of obesity.”

Practical Measures

The researchers suggested that body fat percentage should become the prevailing standard of health, and recommended some convenient and accessible tools for this purpose: skin fold measurements that estimate body fat based on the thickness of the fat layer under the skin, and a user-friendly device measuring the body’s electrical conductivity, already used in many fitness centers.

The gold standard is to use MRI or DXA scans but these are not practical in the clinic, Mr. Gepner said.

An MRI is an imaging technology that produces a detailed three-dimensional image of the body.

The electrical monitoring devices, which give an estimation of the body composition with the help of electrical conductivity, are relatively cheaper and within half a minute can give an estimate of the body composition.

These devices provide a good solution, and although less accurate than DXA, they can still give a better indication of the individual’s fat mass than the BMI index.

“We want to check people in the most correct way,” Mr. Gepner said.

This study is “a wake-up call” for health organizations to switch from the “outdated BMI test” to simple devices that work on electrical conductivity, “to allow early detection and treatment” of obesity, he said.

Treating Obesity

When there is a diagnosis of obesity, precise instructions can be given to change diet, add certain types of physical activity, strength activity to increase muscle mass, and aerobic activity to reduce fat, Mr. Gepner said.

Mr. Lahav said proper nutrition and strength training—rather than aerobic training such as walking, spinning, and jogging—is more important for obese people with regular body weight.

In a previous study, Mr. Gepner and his colleagues showed that even moderate weight loss is accompanied by a significant decrease in fat percentages, meaning “we should not actually focus on weight but on our body composition,” he said.

Electrical conductivity devices are more expensive than regular scales, but in the long run a single device “pays off,” said Mr. Gepner, because it allows for the early detection of obesity that might otherwise be undetected and develop into cardiometabolic diseases such as heart disease, diabetes, fatty liver, kidney dysfunction, and more.

Until the health system and institutions adjust themselves to provide the means to evaluate body composition, he said, people should initiate these tests themselves, either to demand it from their health providers or do it proactively on their own to check their body composition.

The authors recognized several limitations of the study.

The main ones are that the study did not track changes in body composition and cardiometabolic parameters over time, “precluding the establishment of causality,” according to the researchers.

Additionally, although being a large sample size study, it was conducted at only one research center, which potentially restricts inference of the findings to other populations.

See more here theepochtimes

Please Donate Below To Support Our Ongoing Work To Defend The Scientific Method

PRINCIPIA SCIENTIFIC INTERNATIONAL, legally registered in the UK as a company incorporated for charitable purposes. Head Office: 27 Old Gloucester Street, London WC1N 3AX. 

Trackback from your site.