A Mediterranean Diet-Based Culinary Intervention in Adults With Metabolic Syndrome

Changes in metabolic syndrome components according to the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) criteria, including waist circumference, blood pressure, fasting glucose, triglycerides, and HDL cholesterol, measured as continuous variables, using a score ranging from 1 to 5.

Weight in kilograms (kg) using a calibrated electronic scale. Fat mass and lean mass in kilograms (kg) measured using dual-energy X-ray absorptiometry (DXA).

Body fat expressed as a percentage (%) measured using dual-energy X-ray absorptiometry (DXA).

Height, measured in centimeters (cm) using a wall-mounted stadiometer

Lipid profile including total cholesterol (mg/dl), LDL cholesterol (mg/dl), HDL cholesterol (mg/dl), triglycerides (mg/dl), VLDL cholesterol (mg/dl), and non-HDL cholesterol (mg/dl) measured using standard enzymatic methods.

Liver enzymes, including alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), and alkaline phosphatase (ALP), measured in units per liter (U/L) using standard laboratory methods.

Total and direct bilirubin, measured in micromoles per liter (µmol/L) using standard laboratory methods.

Serum albumin and total protein, measured in grams per liter (g/L) using standard laboratory methods.

Glycated hemoglobin (HbA1c), measured as a percentage (%) using standardized laboratory assays.

Dietary intake, assessed using a validated Food Frequency Questionnaire (FFQ) to estimate habitual energy and nutrient intake. Nutrient and energy intake are expressed in grams per day (g/day), milligrams per day (mg/day), micrograms per day (µg/day), or kilocalories per day (kcal/day), depending on the dietary component evaluated.

Mediterranean diet adherence, assessed using the 14-item Mediterranean Diet Adherence Screener (MEDAS). Scores range from 0 to 14, with higher scores indicating greater adherence to the Mediterranean diet.

Culinary habits, assessed using the Home Cooking Frequency Questionnaire (HCFQ). The questionnaire evaluates the frequency of home cooking, food preparation behaviors, and culinary skills. Higher scores indicate greater frequency of home cooking and healthier culinary practices.

Reduced and oxidized glutathione (GSH and GSSG), measured in micromoles per liter (µmol/L) using enzymatic or chromatographic methods.

Gut microbiota composition, assessed by 16S ribosomal RNA (16S rRNA) gene sequencing of fecal DNA. Relative abundance of bacterial taxa is expressed as percentage (%).

Superoxide dismutase (SOD), measured in units per milliliter (U/mL) using standardized enzymatic assays.

F2-isoprostanes, measured in picograms per milliliter (pg/mL) using liquid chromatography-tandem mass spectrometry (LC-MS/MS) or enzyme-linked immunosorbent assay (ELISA).

Malondialdehyde (MDA), measured in micromoles per liter (µmol/L) using high-performance liquid chromatography (HPLC) or validated colorimetric assays.

Catalase (CAT), measured in units per liter (U/L) using standardized enzymatic assays.

Inflammatory biomarkers, including tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), monocyte chemoattractant protein-1 (MCP-1), and ghrelin, measured in picograms per milliliter (pg/mL) using multiplex immunoassays or enzyme-linked immunosorbent assay (ELISA).

Adipokines, including leptin and visfatin, measured in nanograms per milliliter (ng/mL) using multiplex immunoassays or enzyme-linked immunosorbent assay (ELISA).

Adiponectin, measured in micrograms per milliliter (µg/mL) using enzyme-linked immunosorbent assay (ELISA).

High-sensitivity C-reactive protein (hs-CRP), measured in milligrams per liter (mg/L) using immunoturbidimetric or immunoassay methods.

Circulating polyphenols and plasma carotenoids, measured in micromoles per liter (µmol/L) using high-performance liquid chromatography (HPLC) coupled with mass spectrometry.

Urinary polyphenols, measured in milligrams of gallic acid equivalents per gram of creatinine (mg GAE/g creatinine) using the Folin-Ciocalteu method or chromatographic techniques.

Advanced glycation end products (AGEs), measured in nanograms per milliliter (ng/mL) using enzyme-linked immunosorbent assay (ELISA).

Fecal short-chain fatty acids (SCFAs), including acetate, propionate, and butyrate, measured in micromoles per gram of feces (µmol/g) using gas chromatography with flame ionization detection (GC-FID).

Health-related quality of life, assessed using the 36-Item Short Form Health Survey (SF-36). Scores range from 0 to 100 for each of the eight domains and the Physical Component Summary (PCS) and Mental Component Summary (MCS) scores, with higher scores indicating better health-related quality of life.

Physical activity, assessed using the International Physical Activity Questionnaire-Short Form (IPAQ-SF). Physical activity is expressed as metabolic equivalent of task (MET)-minutes per week (MET-min/week), with higher values indicating greater levels of physical activity.