Protective role of dietary intervention rich in unsaturated fats in dyslipidemic children

INTERVENTION: The study is an 8‐week randomized, controlled, parallel, single‐blind dietary intervention study. Subjects receive dietary guidelines and individually randomized to the following three parallel groups of 20 subjects each: Group 1: Children consuming hazelnuts with skin as snack (between 15‐30 g per day, based on body weight) Group 2: Children consuming hazelnuts without skin as snack (between 15‐30 g per day, based on body weight) Group 3: Children who do not consume nuts (or children consuming other sources of unsaturated fats) At the beginning and at the end of the intervention (t= 8 weeks), blood and stool samples are collected and used to evaluate the oxidative stress related markers (e.g. DNA damage, oxidized LDL, PON‐1 concentration, etc.), the serum lipid profile and erythrocyte membrane phospholipids composition. In addition, dietary and metabolic markers (e.g. microbiota composition, inflammatory related markers, etc.) are analysed. CONDITION: Familiar dyslipidemia ; Nutritional, Metabolic, Endocrine PRIMARY OUTCOME: Endogenous oxidized DNA bases (using enzyme formamidopyrimidine‐DNA glycosylase) measured by Comet assay in peripheral blood mononuclear cells at baseline (t=0) and at the end of intervention (t=8 weeks) SECONDARY OUTCOME: 1. Changes in serum lipid profile triglycerides, total cholesterol, high density lipoprotein (HDL)‐cholesterol, low density lipoprotein (LDL)‐cholesterol; 2. Changes in erythrocyte phospholipids composition; 3. Changes in anthropometric characteristics (age, weight, height, body mass index); 4. Changes in blood pressure (diastolic and systolic blood pressure); 5. Changes in oxidized LDL and paraoxonase 1 (PON‐1); 6. Changes in markers of inflammation; 7. Changes in microbiota composition; All assessed at baseline and at the end of intervention (8 weeks) INCLUSION CRITERIA: 1. Children aged 5‐17 years affected by primary dyslipidemia (familiar hypercholesterolemia, familiar combined hyperlipidemia and undefined hypercholesterolemia), 2. Total cholesterol and/or triglycerides value higher than their age‐ and sex‐specific 90th percentile 3. Body mass index (BMI) <95th percentile