Cardiometabolic Abnormalities among Normal-Weight Adults: Prevalence and Associated Sociodemographic and Lifestyle Factors in a Large Spanish Cohort.

Background

Although body mass index (BMI) is widely used to assess obesity-related health risks, it may fail to detect individuals with normal weight who present with significant cardiometabolic abnormalities. This phenotype, often overlooked in clinical practice, is associated with increased risk of cardiovascular disease and type 2 diabetes.

Objective

To assess the prevalence and determinants of cardiometabolic abnormalities in a large cohort of Spanish adults with normal BMI and to explore their associations with sociodemographic and lifestyle variables.

Methods

This cross-sectional study included 163,254 workers aged 18-69 years who underwent occupational health examinations between 2021 and 2024. Only individuals with a BMI between 18.5 and 24.9 kg/m² were included. Cardiometabolic abnormalities were defined as the presence of hypertension, dyslipidemia, or hyperglycemia. Sociodemographic data, smoking status, alcohol intake (measured in standard drinking units), physical activity (assessed with the IPAQ), and Mediterranean diet adherence (assessed using the MEDAS-14 questionnaire) were collected. Multivariate logistic regression analyses were performed to identify factors associated with the presence of one or more cardiometabolic abnormalities.

Results

Among normal-weight adults, 49.0% presented at least one cardiometabolic abnormality. The prevalence was higher in men (54.3%) than in women (44.5%). Cardiometabolic risk was significantly higher among men, older individuals, smokers, those with low physical activity, poor adherence to the Mediterranean diet, and high alcohol consumption. Lower occupational social class was also associated with greater risk. The likelihood of presenting ≥1 cardiometabolic abnormality increased progressively with the accumulation of unhealthy lifestyle habits.

Conclusions

A substantial proportion of normal-weight individuals exhibit cardiometabolic abnormalities, underscoring the need to move beyond BMI in clinical risk stratification. Preventive strategies should incorporate metabolic screening and lifestyle assessments for all individuals, regardless of weight status, to identify those at silent cardiometabolic risk.