Olive Leaf Extract, Meta-inflammation, Anxiety, and Excess Weight

Overview

Excess Weight is accompanied by a process that produces a low-grade inflammation state, called meta-inflammation. Anxiety is also associated with inflammation. Inflammation is closely related to oxidative stress. Both processes help perpetuate each other. Olive Leaf Extract (OLE) is known for having anti-inflammatory and antioxidant effects; by this means, its anxiolytic effect has been proved in animal models. The purpose of this investigation is to evaluate the anti-inflammatory and anxiolytic effects associated with the supplementation of OLE at a daily dose of 750mg (20% oleuropein) for 3 months.

A randomized double-blind placebo clinical trial is proposed. Study groups will be comprised of women living with excessive weight from the Guadalajara Metropolitan Area who meet the following criteria: age ≥18- ≤40 years, body mass index (BMI) ≥25- ≤40 kg/m\^2, blood pressure ≤ 129 mmHg systolic and ≤80 diastolic; anxiety symptomatology score 6 to 14 (mild) according to Hamilton Anxiety Scale (HAS). 70 women at the University Center for Health Sciences (CUCS) from Universidad de Guadalajara who meet inclusion criteria will be invited to participate. Two groups will be randomly formed consisting of 35 women with excessive weight and anxious symptoms each (by the BMI and HAS score, respectively); 35 will receive cellulose (100 mg) as a placebo, and the other 35, 750 mg/day of Olive Leaf Extract (OLE) orally, daily, for 90 days. Participants would be instructed to consume it after breakfast without modifying their eating patterns. Anxious symptomatology will be measured by HAS and Beck Anxiety Inventory (BAI), alternately, every 30 days for 90 days; at the beginning, it would be HAS, after 30 days, investigators will apply BAI, then, after the next thirty days HAS (day 60) and, finally, will end the study applying BAI (day 90). Alternation of these tests is done to avoid bias in patients that allows them to recognize answers to obtain better scores. Treatment adherence will be reviewed on a biweekly basis. At the same time, biweekly, participants will have to fill out a nutritional 24-hour food recall and a food frequency questionnaire and will also be asked if it is their desire to keep participating or not in the investigation. To evaluate meta-inflammation, levels of leptin, IL-6, TNF-α, and cortisol in serum will be quantified using the ELISA technique. This will be done by doing a blood extraction at the beginning and another one at the end of the study (day 90). These two extractions will also be used to measure the patient's lipid profile (LDL cholesterol; LDL-c, total cholesterol; TC, triglycerides; TG and HDL-cholesterol; HDL-c) and glycosylated hemoglobin. At the beginning of the study, investigators will apply a nutritional clinic history that contains information on eating habits (24-hour recall and food frequency), clinical history, and family health history. Anthropometric parameters such as weight, height, age, and BMI will be recorded; also, the percentage of body fat and muscle through bioimpedance. Height will be measured with a stadiometer. Weight and components associated with excessive weight such as percentage of body fat and muscle will be recorded monthly using an Omron® HBF-514C bioimpedance scale.