# Sex differences in metabolic syndrome among U.S. adolescents, NHANES 1999–2020

## TL;DR

This study finds that male U.S. adolescents have a higher prevalence of metabolic syndrome and more metabolic risk factors than females, with no significant changes over 20 years.

## Contribution

The study reveals sex-specific patterns in metabolic syndrome among U.S. adolescents using a large, nationally representative dataset.

## Key findings

- Male adolescents had a higher metabolic syndrome prevalence (6.1%) compared to females (4.1%).
- Males showed higher rates of elevated blood pressure, fasting glucose, and triglycerides, while females had higher abdominal obesity and low HDL-C.
- Sex disparities in metabolic syndrome were consistent across various subgroups, including age, obesity status, and income.

## Abstract

Metabolic syndrome (MS) poses a growing threat to adolescent health, yet its sex-specific patterns remain inadequately characterized. This study aimed to investigate sex differences in MS prevalence, risk factor clustering, and metabolic phenotypes among U.S. adolescents.

We analyzed cross-sectional data from 6,989 adolescents aged 12–19 years, representing 30.97 million U.S. adolescents, from the National Health and Nutrition Examination Survey (1999–2020). MS was defined based on abdominal obesity, elevated blood pressure, hyperglycemia, and dyslipidemia, using weighted analyses to account for complex survey design.

The overall MS prevalence was 5.1%, with a significantly higher prevalence in males than in females (6.1% vs. 4.1%, P = 0.017). Critically, no significant temporal trends in MS prevalence were observed over the 20-year period for either sex. Males accumulated more metabolic risk factors than females, showing higher rates of elevated BP (5.9% vs. 0.9%), fasting glucose (22.7% vs. 10.4%), and triglycerides (8.8% vs. 6.4%), whereas, females had higher prevalences of abdominal obesity (25.9% vs. 12.6%) and low HDL-C (22.8% vs. 18.8%). Moreover, metabolically unhealthy obesity was more common in males (13.7% vs. 10.0%). Subgroup analyses showed significant sex disparities persisted among ages 12–15, obese, non-Hispanic White, and high-income subgroups. Sensitivity analyses using alternative definitions, including waist-to-height ratio for abdominal obesity, robustly confirmed the male predominance in MS prevalence.

Male U.S. adolescents exhibited a higher MS prevalence and a more unfavorable aggregation of metabolic risk factors than females. The stability of MS prevalence over the two-decade period highlighted the need for sex-specific and developmentally targeted interventions, especially within identified high-disparity subgroups.

The online version contains supplementary material available at 10.1186/s13098-025-02052-5.