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Effect of Nutritional Intervention and Olive Oil in Severe Obesity

Not Applicable
Completed
Conditions
Severe Obesity
Interventions
Behavioral: Nutritional intervention
Other: Nutritional intervention plus olive oil
Dietary Supplement: Olive oil
Registration Number
NCT02463435
Lead Sponsor
Universidade Federal de Goias
Brief Summary

Obesity is a worldwide epidemic with increasing prevalence, specially severe obesity (Body Mass Index (BMI) ≥ 35 kg/m2). It is a multifactorial disease that involves genetic and environmental factors that lead to increased mortality from cardiovascular disease, diabetes, cancer, among others and impairs life quality. Most research on severe obesity focuses on surgical alternatives and their results, thus this clinical trial aims to evaluate the effect of a non-pharmacological approach based on nutritional intervention and supplementation with a functional food, the olive oil. It will analyze the effectiveness of interventions on: weight loss, improvements on body composition and inflammatory profile (TNF-alfa, interleucins 1, 6 and 10, adiponectin), insulin resistance and serum lipids control, changing eating habits and physical activity practice, modification on bone mineral density and sarcopenia, and reduction of cardiovascular risk and other diseases. Also, it will be investigated the influence of polymorphisms (Pro12Ala of PPAR-γ gene, -174G\>C of IL6 gene e Trp64Arg of ADRB3 gene) on nutritional intervention effectiveness with and without olive oil. This research looks for improving severely obese patient's care and contributing to effective results by reducing costs and risk treatment. The investigators believe that this informations will contribute significantly to the scientific field, expanding the knowledge about severe obesity.

Detailed Description

After enrollment, patients undergo a diagnostic phase (baseline) with nutritional, anthropometric and body composition assessment (multifrequency bioelectrical impedance analysis and dual X-ray absorptiometry); investigation of clinical history; collecting blood samples; carotid artery intima-media thickness, heart rate variability and accelerometry assessments; and application of validated questionnaires to evaluate secondary outcomes. Patients will be randomized into three different treatment groups. Randomization will be stratified according to Body Mass Index (BMI) (BMI between 35 and 39,99 kg/m2 and BMI ≥ 40 kg/m2), allocation ratio 1:1:1 and parallel intervention. Then, trained nutritionists will deliver the intervention according to the patient group and they will be followed-up for 12 weeks, with visits each 4 weeks.

Interventions will be provided as follow:

Olive oil group: in order to evaluate the effect of only the extra virgin olive oil on primary and secondary outcomes, patients will be instructed to maintain habitual food consumption and consume 52 mL of extra virgin olive oil daily (4 sachets per day, 2 at lunch and 2 at dinner).

Nutritional intervention group: patients assigned to this group will receive nutritional intervention consisting of prescription of individualized food plan to reduce 5 to 10% of initial body weight, nutritional counseling for comorbidities and promoting healthy eating habits and physical activity. Resting Energy Expenditure (REE) will be calculated according to Horie-Waitzberg \& Gonzalez equation developed for severe obese individual using current weight and lean body mass (Horie et al., 2011). Total energy expenditure (TEE) will be calculated multiplying REE by activity factor recommended by Institute of Medicine (Trumbo et al., 2005) and thermic effect of food (Hill, Wyat, Peters, 2012). Total energy value (TEV) of diet will be determined reducing 550 to 1100 kcal from TEE to reach 0.5 to 1.0 weekly weight reduction according to the patient's individual goal. Distribution of macronutrients will follow Dietary Reference Intake (DRI) recommendation: 45-65% of carbohydrates, 10-35% of proteins and 20-35% of lipids (Trumbo et al., 2002). Fat acids (FA) will be distributed as recommended by Sociedade Brasileira de Cardiologia (Sposito et al., 2007): ≤ 7% saturated FA, ≤ 20% monounsaturated FA and ≤ 7% polyunsaturated FA. Food plan prescription will distribute TEV in 4-6 meals. Motivation will be held to changing eating and lifestyle habits.

Nutritional intervention plus olive oil: this group will receive conventional intervention plus supplementation of 52 mL of extra virgin olive oil daily (4 sachets per day, 2 at lunch and 2 at dinner).

At the end of follow-up the same assessments performed at diagnostic phase will be held.

To detect a reduction of 10 kg, with standard deviation of 30, which is in agreement with the study of Rodrigues e Silveira (2011), with a two-sided 5% significance level and a power of 80%, a sample size of 50 patients per group will be necessary, given an anticipated dropout rate of 42,9%.

This research will be conducted at a capital of center Brazil, at Unidade de Pesquisa Clínica of Hospital das Clínica/UFG, Faculty of Medicine/UFG.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
229
Inclusion Criteria
  • Body mass index ≥ 35 kg/m2
  • Residence in Goiânia or metropolitan area
  • Patients referred by Secretaria Municipal de Saúde to Severe Obese Nutrition Clinic
Exclusion Criteria
  • To have already performed bariatric surgery
  • Pregnancy
  • Reduction greater than 8% of body weight in the past 3 months
  • To have been treated at Severe Obesity Nutrition Clinic or have received nutritional counseling in another place in the last 2 years
  • Anti-obesity drugs use
  • Regular utilization of anti-inflammatory drugs or corticosteroids
  • HIV/AIDS, heart failure, kidney failure, hepatic insufficiency, chronic obstructive pulmonary disease and cancer

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Nutritional interventionNutritional interventionPatients under only nutritional intervention for weight loss
Nutritional intervention plus olive oilNutritional intervention plus olive oilPatients under conventional treatment (nutritional intervention) plus extra virgin olive oil supplementation
Olive oilOlive oilPatient under habitual food consumption plus extra virgin olive oil supplementation
Primary Outcome Measures
NameTimeMethod
Body composition changeBaseline, week 12

Body fat mass (BFM), body fat percentage (%BF) and body mass density (BMD) will be evaluated to assess body composition change. BFM and %BF will be assessed using multifrequency bioelectrical impedance analysis (BIA) and dual energy X-ray absorptiometry (DXA) and BMD will be assessed using DXA.

Anthropometric measurements changeBaseline, week 12

Measurements of weight, arm circumference and Body Mass Index (BMI) will be evaluated to assess anthropometric change.

Secondary Outcome Measures
NameTimeMethod
Change in kidney functionBaseline, week 12

Creatinine, urea and uric acid

Change in cardiovascular risk using Framingham Risk Score (FRS)Baseline, week 12
Change in physical activity practice using Global Physical Activity QuestionnaireBaseline, week 12
Change in liver functionBaseline, week 12

AST and ALT

Change in vitaminsBaseline, week 12

Vitamin D, vitamin B12 and folic acid

Change in cardiovascular risk using Global Risk Score (GRS)Baseline, week 12
Polymorphism -174G>C of Interleukin 6 (IL6) gene.Baseline, week12

Difference in responses between intervention groups for anthropometric measurements (weight, arm circumference and body mass index) and body composition variables (body fat mass and body fat percentage) according to this polymorphism

Change in inflammation parametersBaseline, week 12

Neutrophil to lymphocyte ratio (NLR) and lymphocyte to monocyte ratio (LMR)

Change in thyroid functionBaseline, week 12

TSH, T4 and parathyroid hormone

Change in metabolic parametersBaseline, week 12

Lipid profile (total cholesterol, LDL-c, HDL-c, VLDL-c), insulin resistance (HOMA-IR, glycated hemoglobin), fasting glycaemia, hemogram

Change in mineralsBaseline, week 12

Iron, calcium, sodium, potassium and zinc

Change in physical activity practice using accelerometryBaseline, week 12
Change in obesity sarcopenia using muscle mass (evaluated using DXA)Baseline, week 12
Change in sarcopenia using usual gait speedBaseline, week 12
Adherence to nutritional interventionBaseline, week 12

It will be evaluated through changes in food consumption (food frequency questionnaire)

Change in cardiovascular risk using Homocystein levelBaseline, week 12
Polymorphism Pro12Ala of Peroxisome Proliferator-Activated Receptor Alfa (PPAR-alfa)Baseline, week12

Difference in responses between intervention groups for anthropometric measurements (weight, arm circumference and body mass index) and body composition variables (body fat mass and body fat percentage) according to this polymorphism

Change in obesity sarcopenia using handgrip strengthBaseline, week 12
Adherence to the health serviceBaseline, week 12

It will be evaluated through attendance to the clinic visits

Change in symptoms of binge eating disorderusing Binge Eating Disorder ScaleBaseline, week 12
Change in cardiovascular risk using heart rate variability (HRV)Baseline, week 12
PolymorphismTrp64Arg of Beta-3 Adrenergic Receptor (ADRB3) geneBaseline, week12

Difference in responses between intervention groups for anthropometric measurements (weight, arm circumference and body mass index) and body composition variables (body fat mass and body fat percentage) according to this polymorphism

Change in food intake using Food Frequency QuestionnaireBaseline, week 12
Change in food intake using 24 hour recallBaseline, week 12
Change in bone health parametersBaseline, week 12

Change in the following variables: bone density using DXA, falls and fractures and sun exposure

Change in symptoms of anxiety and depression using Hospital Anxiety and Depression ScaleBaseline, week 12
Change in musculoskeletal pain using Visual Analog ScaleBaseline, week 12
Change in musculoskeletal pain using Nordic Musculoskeletal QuestionnaireBaseline, week 12

Trial Locations

Locations (1)

Unidade de Pesquisa Clínica do Hospital das Clínicas/UFG

🇧🇷

Goiânia, Goiás, Brazil

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