The study found that both underweight individuals (BMI below 18.5) and those with severe obesity (BMI 40 and above) have higher mortality risks, with underweight individuals nearly three times more likely to die and severely obese individuals over twice as likely compared to those with a BMI of 22.5-<25.

The findings highlight that BMI alone is insufficient to assess health risks, emphasizing the importance of fat distribution, particularly visceral fat, which has significant metabolic implications.

Interestingly, individuals with a BMI of 25–30 (overweight) and 30–35 (moderate obesity) had similar mortality risks to the reference group, indicating a possible 'fat but fit' phenomenon.

A recent Danish study presented at the European Association for the Study of Diabetes challenges traditional views on BMI and mortality, suggesting that being overweight or even obese does not necessarily increase the risk of early death.

Visceral fat, especially around the abdomen, can increase the risk of metabolic diseases like type 2 diabetes and hypertension, even at the same BMI, underscoring the need for personalized obesity treatment based on fat distribution and health conditions.

The study adjusted for various factors such as sex, comorbidities, and education level, and found consistent results across different age, sex, and education groups.

Researchers acknowledge potential limitations, including reverse causation, where underlying illnesses might cause weight loss and skew mortality data, especially since the sample consisted of individuals undergoing health scans.

Overall, the study emphasizes the importance of personalized approaches to obesity treatment, considering factors like fat distribution and metabolic health rather than relying solely on BMI.