A report argues that the BMI alone is too simplistic to define obesity.
The Lancet Commission on Obesity and has published a report in The Lancet Diabetes and Endocrinology that argues for a split definition of obesity.
The term “clinical obese” should only be applied to patients who have a medical condition that is caused by their weight. “Pre-clinically overweight” should apply to people who are still fat, but healthy, yet at risk of developing disease, according the commission.
The commission said that relying solely on BMI, which determines if someone is at a healthy weight for his or her height, to determine obesity was too simplistic.
The commission stated that “current BMI-based measures can underestimate or overestimate obesity and provide insufficient information about individual health.”
A commission organised by the medical journal in partnership with King’s Health Partners, and supported by over 75 medical organizations around the globe, has called for a nuanced approach.
It should be based not only on the body mass index (BMI), but also on objective signs and symptoms that indicate ill health.
The expert group was chaired by Professor Francesco Rubino from King’s College London. He said that some individuals with obesity maintain normal organ function and overall health over the long-term, while others show signs and symptoms of serious illness right now.
“By defining obesity as a risk, rather than a disease, we can deny people with ill health who are obese the timely care they need.” A blanket definition of obesity can lead to overdiagnosis, unwarranted medication and surgical procedures and potentially harming individuals and causing staggering costs for society.
Our reframing allows for personalised treatment and acknowledges the reality of obesity. It includes access to timely evidence-based treatment for individuals with clinical weight gain, just as it would be for someone with a chronic illness, and risk-reduction strategies for those who are pre-clinical obese, with an increased risk of health but no ongoing disease. This will allow for a more rational allocation of resources in healthcare and a medically-meaningful prioritisation of treatment options,” Professor Rubino said.
The authors of the commission recommend that, while BMI can be used as a screening tool for identifying people who may have an overweight condition, it should not be used to diagnose obesity. They recommend that excess fat be confirmed and distributed around the body by using the following methods.
- In addition to the BMI, you should also measure your waist circumference or waist-to hip ratio (or waist-to height ratio).
- Regardless of BMI, you should measure your waist circumference and waist-to hip ratio (or waist-to height ratio).
- Direct measurement of body fat (such as a DEXA or bone densitometry scan) without regard to BMI.
- When BMI is very high (for example, >40kg/m2), excess body fat may be assumed.
The commission stated that clinical obesity should be defined in this context as a condition characterized by objective signs and/or symptomatic of decreased organ function or a significantly reduced ability to perform standard daily activities such as bathing and dressing, eating, and continence due to excessive body fat.
Clinical obesity is a chronic illness that requires ongoing management and treatment. Pre-clinical weight gain, on the other hand, is a condition that has normal organ function.
Pre-clinical obese people do not suffer from any ongoing illnesses, but they are at a higher risk for developing clinical obesity, as well as other non-communicable conditions in the future. These include type 2 diabetes and cardiovascular disease. They may also be more susceptible to mental disorders and certain types of cancer. The commission recommends that they be given support to help reduce their risk of developing potential diseases.
The new diagnostic criteria of the commission fill in a hole when it comes to diagnosing obesity, as they allow clinicians and doctors to distinguish between health and disease at an individual level,” Dr Gauden Galala from the regional office of the World Health Organization for Europe said.
Galea said, “We hope the wide acceptance of the new framework for diagnosing obesity by important scientific societies around the globe will ensure that systematic clinical assessment becomes a requirement within health systems worldwide.”
