High Phenolic Olive Oil for Enhancing Metabolic Health: a Randomized-controlled Trial in Patients With Central Obesity
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 入组人数
- 80
- 试验地点
- 1
- 主要终点
- Statistically significant change of blood triglyceride levels between the two olive oil groups at the trial endpoint.
研究概览
简要总结
Olive oil is a fundamental component of the Mediterranean diet and a major source of monounsaturated fatty acids with well-established cardioprotective properties. When rich in phenolic compounds-such as hydroxytyrosol, tyrosol, oleuropein, oleocanthal, oleacein, and ligstroside aglycone-it is considered a functional food with antioxidant, anti-inflammatory, cardioprotective, chemoprotective, and neuroprotective effects. According to EU Regulation 432/2012, daily consumption of 20 g of extra virgin olive oil containing at least 5 mg of hydroxytyrosol and tyrosol derivatives (250 mg/kg) contributes to the protection of blood lipids from oxidative stress and qualifies for a health claim.
Overweight/obesity, characterized by excessive fat accumulation, is strongly associated with non-communicable diseases, including cardiovascular disease, type 2 diabetes, hypertension, certain cancers, and neurodegenerative disorders. Chronic low-grade inflammation and oxidative stress are key mechanisms underlying obesity-related metabolic disorders. Although dietary energy restriction remains the primary approach for weight management, growing research interest focuses on natural products rich in phenolic compounds as potential modulators of molecular pathways involved in central obesity.
However, robust clinical evidence in humans with central obesity and metabolic abnormalities remains limited. Therefore, this double-blind, randomized, controlled trial aims to investigate the effects of extra virgin, high-phenolic olive oil (HPOO) compared with low-phenolic olive oil (LPOO) in adults with overweight/obesity with metabolic abnormalities. Participants will consume the assigned olive oil type (HPOO or LPOO) for eight weeks.
At baseline and trial endpoint (8 weeks), data collection will include anthropometric measurements, dietary intake, biochemical indices, inflammatory and oxidative stress markers in blood samples, hormones, bioavailability of phenolic compounds, as well as lifestyle parameters i.e., health-related quality of life, physical activity levels, sleep quality. Ethical approval, informed consent, and data protection procedures will be strictly followed. Statistical analyses will be conducted using SPSS software (SPSS Inc, ΙΒΜ, Chicago, IL, USA).
The study is anticipated to explore whether consumption of high-phenolic olive oil favorably modulates markers related to obesity and metabolic abnormalities, while also improving nutritional status and quality-of-life parameters.
详细描述
Materials and methods The present study is designed as a double-blind, randomized, controlled clinical trial. A total of 70-80 adult men and women (>18 years old) with overweight or obesity (BMI >25 kg/m² and waist circumference >94 cm for men and >80 cm for women) and at least one metabolic abnormality (dyslipidemia, arterial hypertension, insulin resistance, or type 2 diabetes mellitus) will be recruited.
Individuals will be excluded if they are currently taking dietary supplements (e.g., multivitamin preparations), suffer from acute or chronic diseases (e.g., cancer, autoimmune disorders, insulin-treated diabetes), follow a strict vegetarian/vegan diet, abuse alcohol and/or illicit substances, or decline to provide written informed consent.
Participants will be instructed to consume daily, for a total duration of eight weeks either high phenolic olive oil (HPOO), containing >1000 mg/kg total polyphenols, or low phenolic olive oil (LPOO), containing ≤100 mg/kg total polyphenols. The quantity of olive oil administered will be determined based on individual fat energy requirements, aiming to promote mild weight loss.
Participants will be allocated to one of the two intervention groups using simple randomization (1:1), conducted by an independent researcher. Both groups will receive standardized dietary guidance for mild weight loss according to the National Dietary Guidelines to ensure homogeneity of the intervention.
Measurements and data collection will be conducted at baseline and at the end of the intervention (week 0 and week 8), during morning visits following an overnight fast, at the University facilities:
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- 18 Years 至 80 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Adult men and women 18-80 years of age,
- •Overweight/obesity (body mass index > 25 or waist circumference >94 cm for males and >80 cm for females), and
- •The presence of at least one of the following metabolic abnormality: (1) triglyceride level ≥150 mg/dL or HDL cholesterol ≤40 mg/dL in men and ≤50 mg/dL in women; (2) increased blood pressure ≥ 130/85 mm Hg; (3) elevated fasting blood sugar ≥100 mg/dL; (4) standardized drug treatment regimen, and
- •Provided signed informed consent for participation.
排除标准
- •Concomitant acute or chronic disease (e.g., infection, cancer, chronic heart failure, kidney disease, autoimmune diseases like rheumatoid arthritis, inflammatory bowel diseases, Hashimoto),
- •Untreated diabetes,
- •Women at pregnancy or lactation,
- •Individuals with psychiatric or mental disorder,
- •Any use of antioxidant-phytochemical rich supplement, anti-, pre- or probiotics pre-intervention,
- •Drug and/or alcohol abuse,
- •Those who did not consent or were unable to provide consent.
研究组 & 干预措施
Control arm
Participants assigned to the control arm receive olive oil with a low content in phenolic compounts.
干预措施: Low phenolic olive oil (Other)
Intervention arm
Participants assigned to the intervention arm receive extra virgin olive oil rich in phenolic compounds.
干预措施: High phenolic olive oil (Other)
结局指标
主要结局
Statistically significant change of blood triglyceride levels between the two olive oil groups at the trial endpoint.
时间窗: Trial endtpoint (8 weeks)
次要结局
- Statistically significant change of blood pressure between the two olive oil groups at the trial endpoint.(Trial endpoint (8 weeks))
- Statistically significant change of fasting glucose levels between the two olive oil groups at trial endpoint.(Trial endpoint (8 weeks))
- Statistically significant change of low-density lipoprotein (LDL) levels between the two olive oil groups at trial endpoint.(Trial endpoint (8 weeks))
研究者
Aristea Gioxari
Assistant Professor in "Clinical Nutrition and Macronutrient Metabolism"
University of Peloponnese