Composite Dietary Antioxidant Index and Metabolic Health in Overweight/Obesity in U.S. Adults: Evidence From NHANES: 2003-2020

Overweight/Obesity Assessed by Body Mass Index (BMI)

时间窗: Baseline: Data collection for calculating BMI occurs during the specific NHANES survey cycle relevant to this study (single - time - point cross - sectional assessment).

Body Mass Index (BMI) will be calculated as weight (in kilograms) divided by the square of height (in meters). According to the World Health Organization's classification, a BMI of 25.0 - 29.9 kg/m² is considered overweight, and a BMI of 30.0 kg/m² or higher is considered obese. Data on weight and height will be obtained from the NHANES dataset.

Metabolic Phenotype Classification (Metabolically Healthy vs. Unhealthy) Assessed by NCEP ATP III Metabolic Syndrome Components

时间窗: Baseline: Data on metabolic components for phenotype classification will be collected during the corresponding NHANES survey cycle for this study, reflecting a single-time-point cross-sectional assessment.

Metabolic phenotypes are classified as metabolically healthy or unhealthy based on the components of metabolic syndrome defined in the third report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III). Waist circumference data is not used in this classification due to its high correlation with BMI. A participant is defined as metabolically healthy if they have none or only one of the following four metabolic abnormalities: (1) Serum triglycerides (TG) ≥ 150 mg/dL; (2) Serum high-density lipoprotein cholesterol (HDL-C) \< 40 mg/dL in men or \< 50 mg/dL in women; (3) Fasting glucose ≥ 100 mg/dL or use of hypoglycemic drugs; (4) Blood pressure ≥ 130/85 mmHg or use of antihypertensive drugs. A participant is defined as metabolically unhealthy if they have two or more of the above metabolic abnormalities. Relevant data will be retrieved from the NHANES database.