Cut‐off Point of BMI and Obesity‐Related Comorbidities and Mortality in Middle‐Aged Koreans

TLDR

The classification of overweight in Asian populations using a lower BMI threshold has been controversial, yet the rapidly growing number of individuals with BMI ≥ 25 poses substantial disease risks. The study aimed to determine whether a lower BMI cut‑off better identifies health risks in Koreans by analyzing disease and mortality outcomes in a large cohort, and to recommend a BMI of 25 as a prevention threshold. The cohort study tracked 773,915 adults aged 30‑59 over 8‑10 years, measuring changes in obesity prevalence, disease incidence, and all‑cause mortality, noting a steady rise in overweight prevalence and a modest increase in obesity prevalence. Dose‑response links between BMI and hypertension, type 2 diabetes, and hypercholesterolemia emerged at lower BMI levels than in previous studies, yet Koreans with BMI ≥ 25 did not show higher disease or mortality risks than whites, indicating that a lower BMI cut‑off.

Abstract

The need for a lower BMI to classify overweight in Asian populations has been controversial. Using both disease and mortality outcomes, we investigated whether lower BMI cut-off points are appropriate for identifying increased health risk in Koreans.We conducted a cohort study among 773,915 men and women from 30 to 59 years old with 8- to 10-year follow-up periods. Primary outcomes were change of obesity prevalence, obesity-related disease incidence, and all-cause mortality.Prevalence of overweight (BMI of 25.0-29.9) has steadily increased (1.3% annually), whereas obesity (BMI > or = 30) showed a lower prevalence and only a slight increase (0.1%-0.2% annually). Our study revealed that dose-response relationships exist between obesity and related disease incidences (hypertension, type 2 diabetes, and hypercholesterolemia) beginning at lower BMI levels than previously reported. Compared with those in the healthy weight range, Koreans with a BMI > or = 25 were not at greater risk of hypertension, type 2 diabetes, or hypercholesterolemia than has been reported for whites in similar studies. Obesity-related all-cause mortality also did not seem so different from that of whites.Our findings did not support the use of a lower BMI cut-off point for defining overweight in Koreans compared with whites for the purpose of identifying different risks. However, populations with BMI > or = 25 are rapidly increasing and have substantial risks of diseases. To preempt the rapid increases in obesity and related health problems that are occurring in Western countries, Korea should consider using a BMI of 25 as an action point for obesity prevention and control interventions.