A multinational team of researchers has discovered that over 20% of adults with a normal BMI range experience levels of abdominal obesity that puts them at higher risk of hypertension, diabetes, high total cholesterol, and elevated triglycerides.
Cardiometabolic disorders rank among the leading causes of death and disability worldwide. Over the past three decades, cardiovascular disease cases rose from 271 million to 523 million, with disability-adjusted life-years nearly doubling.
Abdominal obesity, especially visceral fat, disrupts metabolic processes via inflammatory pathways that contribute to insulin resistance, dyslipidemia, high blood pressure, and impaired glucose regulation. Diabetes affected an estimated 828 million adults in 2022.
BMI often fails to capture actual fat distribution, and studies have reported greater cardiovascular risk and mortality among individuals with normal BMI but higher waist circumference.
In the study, “Cardiometabolic Outcomes Among Adults With Abdominal Obesity and Normal Body Mass Index,” published in JAMA Network Open, researchers used a cross-sectional design to investigate the global prevalence of normal-weight abdominal obesity and its association with cardiometabolic outcomes.
Data came from the World Health Organization Stepwise Approach to Surveillance of Noncommunicable Disease Risk Factors (WHO STEPS) surveys in 91 countries between 2000 and 2020, including 471,228 participants aged 15 to 69 years across Africa, the Americas, the Eastern Mediterranean, Europe, Southeast Asia, and the Western Pacific.
Abdominal obesity was defined as high waist circumference (≥80 cm in women; ≥94 cm in men). Normal-weight abdominal obesity combines normal BMI (18.5–24.9) with high waist circumference. The main outcomes were hypertension, diabetes, high total cholesterol, and high triglycerides. Measurements were via standardized interviews, physical body measures, and biochemistry.
Across the global dataset, abdominal obesity was associated with several behavioral and metabolic factors. Individuals with larger waist circumferences were more likely to report low fruit and vegetable intake (odds ratio [OR] 1.22) and physical inactivity (OR 1.60). Clinically, those with abdominal obesity but a normal body mass index showed higher odds of hypertension (OR 1.29), diabetes (OR 1.81), high total cholesterol (OR 1.39), and high triglycerides (OR 1.56).
Intriguingly, higher education trended toward higher odds of the presence of abdominal obesity, with primary education (OR 1.53) and secondary or higher education (OR 2.38) raising the risk compared with no formal schooling. Africa was the lone exception with secondary and higher education associated with lower odds (OR 0.64).
Across the pooled sample, 21.7% of participants with normal BMI had abdominal obesity, ranging from 15.3% in the Western Pacific region to 32.6% in the Eastern Mediterranean region. Lebanon showed the highest country-level prevalence at 58.4%, and Mozambique the lowest at 6.9%.
Adults with a normal BMI but enlarged waist circumference faced higher odds of adverse metabolic conditions compared with peers of normal BMI without abdominal obesity. Hypertension, diabetes, high total cholesterol (OR 1.39), and high triglycerides showed globally significant increases.
A few regional exceptions were discovered as high total cholesterol was not observed in the Americas, high triglycerides were not found in Europe and hypertension did not rise in the Western Pacific.
The authors conclude that relying solely on BMI may be insufficient to identify high-risk individuals with normal-weight abdominal obesity.