Overview

• Researchers analyzed nearly 86,000 adults in Denmark over about five years and identified the lowest death risk around a BMI of 22.5–24.9.
• Participants with BMI below 18.5 had nearly triple the mortality of the reference group, and those at 18.5–19.9 had roughly double the risk.
• Individuals classified as overweight or moderately obese (BMI 25–35) showed no significant increase in mortality, whereas BMI 40 or higher was associated with about a 2.1-fold rise.
• Authors cautioned that illness-related weight loss could explain higher risk in low‑BMI groups and noted potential selection bias from a cohort of mostly older women who underwent clinical scans.
• Commentary stresses BMI’s limits as a blunt tool and advises against changing guidelines now, though the authors suggest the lowest‑risk range in this dataset may extend up to BMI 30.