Experts Call for Big Change in How Obesity Is Measured

Traditional understandings of obesity may undergo radical change. In a new report published this week, a widely supported group of scientists is pushing for major changes in how obesity is diagnosed and classified.

The report was prepared as part of a commission supported by more than 50 obesity experts from around the world. Lancet. Among other recommendations, the group calls for phasing out body mass index (BMI) as the sole criterion for diagnosing obesity. They also argue that obesity should be divided into two different types depending on how much a person’s condition can harm them.

The commission’s specific goal was to establish objective but nuanced criteria for diagnosing obesity. Currently, obesity is strictly defined by BMI, which is calculated from a person’s weight and height. People with a BMI above 30 are obese, while severe obesity is considered a BMI above 40 (some parts of the world use lower BMI cutoffs to account for population differences in the average size of residents).

While BMI is an easily accessible and trackable measure, it often doesn’t tell the whole picture, commission experts say, a criticism shared by many other public health experts. expressed in the past. Obesity-related harm is primarily caused by excess body fat, and BMI may not adequately correlate with this. A very fit person may have a high BMI but low body fat, for example, a person with a “normal” BMI may carry a risky amount of body fat. The distribution of excess body fat can vary from person to person, and so can the health risks associated with this fat. Excess fat around a person’s waist or around vital internal organs such as the liver and heart is more dangerous than excess body fat on the skin under, for example, our arms or legs.

Experts do not urge doctors to completely abandon BMI as a tool for diagnosing obesity, but rather, it should be used in conjunction with other body measurements. These include measuring people’s waist circumference, their waist-to-hip ratio or waist-to-height ratio. According to the researchers, medical professionals should use at least two measures of body size and another measure other than BMI to diagnose people who are suspected of being obese. Alternatively, doctors can instead collect a direct measurement of a person’s body fat, for example by taking a bone density test, commonly known as a DEXA scan. People with a very high BMI (above 40) can still be assumed to have excess body fat, they added.

“If implemented, people with obesity (BMI near or above obesity) should have at least one body measurement (eg, waist circumference in most cases or DEXA if available) to confirm accurate detection of excess body fat. Confirm that a person is indeed obese and not, for example, a muscular person with a high BMI,” Francesco Rubino Commission, an obesity researcher at King’s College London, told Gizmodo in an email.

Rubino and his commission also recommend that doctors divide obesity into two broad categories: preclinical and clinical obesity. Experts note that high body fat alone may not negatively affect your health, so they’ve created a list of criteria (18 for adults, 13 for children) to determine if someone’s obesity is causing other body problems. A person with obstructive sleep apnea, severe knee pain, or poor cardiovascular health, for example, is classified as clinically obese if it is suspected to be related to excess body fat, such as someone who is obese but has no signs of abnormal organ function. the presence of preclinical obesity.

“The clinical impact of obesity needs to be reconsidered to explain whether obesity can be both a risk factor for other diseases and a direct cause of disease. Therefore, a definition of clinical obesity bridges the gap in the characterization of obesity as a direct health cause and may be an effective way to address widespread misconceptions and biases among patients, healthcare professionals, and policymakers that hinder poor decision-making. the authors in their report has been published on tuesday Lancet Diabetes and Endocrinology.

People with preclinical obesity may still be at risk for future health problems, Rubino says, but the difference allows for more personalized obesity care. However, people with clinical obesity should be treated with effective treatments to reduce weight immediately, including: newer drugs such as semaglutide (the active ingredient in Ozempic and Wegovy) or bariatric surgery, doctors may use a less invasive approach with someone with preclinical obesity, depending on the level of risk.

“These strategies can be as simple as offering monitoring of time and lifestyle changes aimed at possible weight loss for people who are at low risk (even modest weight loss can go a long way to prevent obesity-related diseases) or involve more active forms of weight loss. “The risk of intervention should be assessed as particularly high (due to factors other than obesity itself, such as family history, abdominal fat accumulation, other conditions, overweight, and especially a combination of the above),” Rubino said.

That is what the group’s recommendations ultimately boil down to. But their results are widely endorsed by health-related organizations around the world – 76 in total, including the American Heart Association in the US, the Royal College of Physicians in the UK and the World Obesity Federation. There are important big questions about the nature of obesity that remain to be answered, such as the exact prevalence of obesity from clinic to clinic (more than 1 billion people worldwide are thought to be obese according to the current BMI definition). But according to report co-author Robert Eckel, an endocrinologist at the University of Colorado School of Medicine, the new guidelines should go a long way to helping both doctors and people living with obesity.

“The goal of our work was to optimize and personalize patient diagnosis and risk-adjusted care,” he told Gizmodo. “We think this characterization will be of benefit to patients, healthcare providers, and healthcare providers to monitor.”