It was determined that body mass index alone was not sufficient to determine obesity.

In the study conducted by four research groups in China, England, USA and Spain, data of a total of 844 thousand 108 adults were examined.

In the study, obesity disease was evaluated in two separate categories: "clinical obesity", which causes deterioration in organ functions, and "pre-clinical obesity", which does not yet cause such deterioration.

Accordingly, using body mass index alone caused some people to be misclassified as obese and others to miss the diagnosis of obesity.

Using body mass index alone resulted in 1.2 to 3.1 percent of participants being overclassified as obese and 5.2 to 8.6 percent underclassified.

When waist circumference and waist-to-height ratio were included in the evaluation, the prevalence of obesity increased by 3.3 to 7.4 percent depending on the country.

It was found that 77.4 to 91.3 percent of people with preclinical obesity at baseline did not progress to clinical obesity within 10 years.

It was determined that the risk of death of people with clinical obesity for any reason was 69 percent higher than those without obesity and organ dysfunction. In preclinical obesity, this risk increase was calculated as 19 percent.

In this context, researchers suggested that before diagnosis, body fat ratio should be evaluated with measurements such as waist circumference as well as body mass index, and weight-related organ dysfunctions such as heart or liver problems should be taken into account.

Professor Francesco Rubino, one of the authors of the study, said in his statement: "Body mass index alone cannot show whether a person is currently sick, whether he is at risk of disease, or what kind of care he needs. This can lead to people receiving both inadequate and excessive treatment. While the new definition makes it possible to provide health care that is personalized and proportionate to needs, a uniform definition based only on body mass index prevents this." he said.

The results of the research were published in the journal "Nature".