Proposed obesity redefinition may halve global prevalence, but raises health risks, say researchers

A global study shows that using stricter obesity criteria requiring an existing health issue could drastically reduce obesity rates. Experts warn this could delay diagnosis and give a false sense of health, risking missed opportunities for early intervention and care

New York: An international team of researchers has found that obesity prevalence would shift significantly under proposed new criteria that could hinder the prevention and early detection of serious health conditions.

The study, published in Plos Global Public Health, analysed data from 56 countries to compare the prevalence of pre-clinical and clinical obesity using the existing BMI criteria with what the prevalence would be under the proposed criteria that requires at least one health condition to already be present before a person is considered clinically obese, such as diabetes, hypertension, or high cholesterol.

---

“Obesity is a serious problem and the definitions we use have implications for clinical treatment, health expenditures, disease surveillance, and people’s awareness of their own health risks. So, it is important to understand how much any new definition would impact the prevalence of obesity,” said lead author Rodrigo Carrillo-Larco, assistant professor of global health at Emory University’s Rollins School of Public Health.

The study was authored by researchers from Emory University and Johns Hopkins University in the US, the University of Queensland in Australia, Zhejiang University School of Medicine in China, and Universidad Peruana Cayetano Heredia and Universidad Cientifica del Sur in Peru.

When the additional health issues were included in the criteria for obesity, the prevalence dropped significantly among the 142,250 adults surveyed—with some nations seeing a drop of more than 50 per cent—but the results varied by nation and gender.

For example, the East African nation of Malawi had among the highest decreases in obesity prevalence under the proposed definition, but the decline was uneven among men (68 per cent) and women (53 per cent).

While the new definition could be more aligned with current disease risk, the researchers urged caution before considering a shift in obesity surveillance to the proposed standard because doing so would create substantial challenges in terms of measurement, equity, and implementation. And for individuals who would no longer be considered obese, it could provide a dangerous false sense of security.

“At the population level, we would expect the prevalence of obesity to drop, but we should be mindful that it’s an artificial drop because the new definition is stricter or complex—that reduction in obesity is not real,” Carrillo-Larco said.