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Effect of a Low-calorie Diet With a Prebiotic Supplement on Health of Overweight-obese Subjects.

Not Applicable
Completed
Conditions
Polyphenols
Obesity
Weight Loss
Registration Number
NCT06710106
Lead Sponsor
Clinica Universidad de Navarra, Universidad de Navarra
Brief Summary

The main objective of this project is to evaluate the effect of prebiotic supplementation on weight loss and other physiological and metabolic parameters related to excess weight in overweight/obese adult men and women, as well as to determine the changes in the gut microbiota associated with these changes. Specific objectives are focus on evaluate the effect of the intervention on the following parameters:

* Weight and body composition.

* Changes in the gut microbiota (metagenomics).

* Changes in urinary and serum metabolites.

* Complete blood count, routine biochemical variables related to glucose and lipid metabolism, as well as liver health parameters.

* Specific markers involved in obesity pathology (insulin, leptin, adiponectin, and cytokines MCP1, TNF, CRP, and IL10).

* Satiety-related variables using a visual analog scale.

* Adherence to the assigned intervention, both to the hypocaloric diet and to the supplement provided in the study.

* Physical activity level.

* Changes in gastrointestinal health through self-reported questionnaires.

* Mental health and quality of life of participants through self-reported questionnaires.

* Chronotype of participants through a self-reported questionnaire. For this purpose, a randomized, double blind parallel study has been designed.

Target sample size is 156 subjects.

Participants will be allocated in two groups for 8 weeks:

* Experimental group (n=104): hypocaloric diet + prebiotic supplement.

* Placebo group (n=52): hypocaloric diet + placebo supplement.

Participants will visit nutritional intervention unit at week 1 and week 8. At week 4 they will receive a phone control call.

Detailed Description

Volunteers who wish to participate in the study will be interviewed by phone to verify that they meet the main inclusion criteria. Volunteers who meet the main inclusion criteria will be invited to an information and screening visit to resolve any doubts. Volunteers who agree to participate in the study will sign the informed consent and will be randomly allocated to one of the two arms of the study and will be provided with any required material.

During the intervention, volunteers will attend 2 Clinical investigation visits. The first one will be carried out on the first day of the study and the last one will take place at the end of the 8 weeks. In both visits anthropometric and body composition measurements, blood pressure, stool and blood, urine and stool samples, as well as data about dietary, physical activity, sleep and gastrointestinal symptoms will be taken.

Inclusion criteria

* Men and women aged 18 to 70 years.

* Volunteers with overweight or obesity (BMI: 25.0-39.9 kg/m²) and body fat percentage \> 30% for women / \> 20% for men.

* Stable weight (+/- 5%) in the last three months prior to the start of the study.

* Normal physical examination and vital signs, or clinically insignificant findings for the experiment (those not related to metabolic health).

* Subjects must be able to understand and be willing to sign the informed consent form, agreeing to comply with all study procedures and requirements.

* Continued pharmacological/hormonal treatment will be allowed as long as it does not affect the study parameters and the dosage has been stable for at least 3 months. Exclusion will apply to treatments with insulin or any drug with hypoglycemic effects.

* Willingness to undergo each of the procedures involved in the study (including consuming a sweetened yogurt).

* Availability to attend the two in-person clinical evaluation sessions at the scheduled times and locations.

Exclusion criteria

* Volunteers undergoing pharmacological treatment if the treatment is not stable (at least 3 months before the start of the study), with exclusion of treatments:

* That alter gastrointestinal function.

* Stomach protectants.

* Hypoglycemic drugs.

* Insulin (under no circumstances).

* Subjects with relevant functional or structural abnormalities of the digestive system, such as malformations, angiodysplasias, active peptic ulcers, chronic inflammatory or malabsorption diseases, hiatal hernia, reflux, etc.

* Subjects who have undergone surgical interventions with permanent sequelae in the digestive system (e.g., gastroduodenostomy) or bariatric surgery.

* Suffering from any chronic metabolic disease or obesity-related disease, or any systemic intestinal, liver, or kidney disease: type 1 or 2 diabetes, severe dyslipidemia, uncontrolled thyroid dysfunction, cirrhosis, inflammatory bowel disease, untreated anemia, etc. (non-alcoholic fatty liver will not be an exclusion criterion).

* Exceeding the alcohol consumption limit for the corresponding sex (more than 14 units per week for women and 20 units per week for men).

* Pregnant, breastfeeding, or planning to become pregnant.

* Taking nutritional supplementation (weight loss supplements, fiber supplements, probiotics, multivitamins, etc.) that contains compounds that may affect the study outcomes, unless the person is willing to stop these supplements during the 8-week intervention period and ensures a minimum washout period of 30 days before baseline measurements.

* Having donated blood in the 14 days prior to the start visit.

* Subjects with any type of cancer or undergoing cancer treatment, or who have not been free of cancer for at least 5 years since eradication.

* Subjects with an allergy to any component of the study product or any other food that interferes with and complicates following the study protocol.

* Subjects with any cognitive and/or psychiatric impairment.

* Subjects who are expected to have poor cooperation or, in the investigator's opinion, have difficulty following the study procedures.

* Subjects currently undergoing treatment for weight loss/body composition modification.

* Subjects who are taking or have taken antibiotics within 30 days before the initial visit.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
156
Inclusion Criteria
  • Men and women aged 18 to 70 years.
  • Volunteers with overweight or obesity (BMI: 25.0-39.9 kg/m²) and body fat percentage > 30% for women / > 20% for men.
  • Stable weight (+/- 5%) in the last three months prior to the start of the study.
  • Normal physical examination and vital signs, or clinically insignificant findings for the experiment (those not related to metabolic health).
  • Subjects must be able to understand and be willing to sign the informed consent form, agreeing to comply with all study procedures and requirements.
  • Continued pharmacological/hormonal treatment will be allowed as long as it does not affect the study parameters and the dosage has been stable for at least 3 months. Exclusion will apply to treatments with insulin or any drug with hypoglycemic effects.
  • Willingness to undergo each of the procedures involved in the study (including consuming a sweetened yogurt).
  • Availability to attend the two in-person clinical evaluation sessions at the scheduled times and locations.
Exclusion Criteria
  • Volunteers undergoing pharmacological treatment if the treatment is not stable (at least 3 months before the start of the study), with exclusion of treatments:
  • That alter gastrointestinal function.
  • Stomach protectants.
  • Hypoglycemic drugs.
  • Insulin (under no circumstances).
  • Subjects with relevant functional or structural abnormalities of the digestive system, such as malformations, angiodysplasias, active peptic ulcers, chronic inflammatory or malabsorption diseases, hiatal hernia, reflux, etc.
  • Subjects who have undergone surgical interventions with permanent sequelae in the digestive system (e.g., gastroduodenostomy) or bariatric surgery.
  • Suffering from any chronic metabolic disease or obesity-related disease, or any systemic intestinal, liver, or kidney disease: type 1 or 2 diabetes, severe dyslipidemia, uncontrolled thyroid dysfunction, cirrhosis, inflammatory bowel disease, untreated anemia, etc. (non-alcoholic fatty liver will not be an exclusion criterion).
  • Exceeding the alcohol consumption limit for the corresponding sex (more than 14 units per week for women and 20 units per week for men).
  • Pregnant, breastfeeding, or planning to become pregnant.
  • Taking nutritional supplementation (weight loss supplements, fiber supplements, probiotics, multivitamins, etc.) that contains compounds that may affect the study outcomes, unless the person is willing to stop these supplements during the 8-week intervention period and ensures a minimum washout period of 30 days before baseline measurements.
  • Having donated blood in the 14 days prior to the start visit.
  • Subjects with any type of cancer or undergoing cancer treatment, or who have not been free of cancer for at least 5 years since eradication.
  • Subjects with an allergy to any component of the study product or any other food that interferes with and complicates following the study protocol.
  • Subjects with any cognitive and/or psychiatric impairment.
  • Subjects who are expected to have poor cooperation or, in the investigator's opinion, have difficulty following the study procedures.
  • Subjects currently undergoing treatment for weight loss/body composition modification.
  • Subjects who are taking or have taken antibiotics within 30 days before the initial visit.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Primary Outcome Measures
NameTimeMethod
Fecal microbiotaClinical Investigation Day 1 and Clinical Investigation Day 2

Fecal microbiota of participants will be analyzed by bacterial 16S or Shotgun gene sequencing technology.

Secondary Outcome Measures
NameTimeMethod
Body weightClinical Investigation Day 1 and Clinical Investigation Day 2

Weight of participants will be measured by bioimpedance and reported in kg

HeightClinical Investigation Day 1

Height of participants will be measured by stadiometer and reported in m.

Body mass indexClinical Investigation Day 1 and Clinical Investigation Day 2

Body mass index will be calculated as follows: weight (kilograms)/ height (cm)2

Body fat percentageClinical Investigation Day 1 and Clinical Investigation Day 2

Body fat of participants will be analyzed by bioimpedance and reported in percentage and kilograms.

Body muscle massClinical Investigation Day 1 and Clinical Investigation Day 2

Body muscle mass of participants will be analyzed by bioimpedance and reported in kilograms.

Body lean massClinical Investigation Day 1 and Clinical Investigation Day 2

Body leen mass of participants will be analyzed by bioimpedance and reported in kilograms.

Body water massClinical Investigation Day 1 and Clinical Investigation Day 2.]

Body water mass of participants will be analyzed by bioimpedance and reported in kilograms.

Body bone massClinical Investigation Day 1 and Clinical Investigation Day 2

Body bone mass of participants will be analyzed by bioimpedance and reported in kilograms.

Gastrointestinal symptomsClinical Investigation Day 1 and Clinical Investigation Day 2

Gastrointestinal symptoms will be registrated through Gastrointestinal Symptoms Rating Scale questionnaire, which is a questionnaire of 15 items. The questionnaire has a seven-point graded likert-type scale, where 1 represents absence of troublesome symptoms and 7 represents very troublesome symptoms.

Dietary intakeClinical Investigation Day 1 and Clinical Investigation Day 2

Dietary intake (energy, macronutrients and micronutrients) will be analysed by food frequency questionnaire.

Physical activityClinical Investigation Day 1 and Clinical Investigation Day 2

Physical activity will be evaluated by the reduced version of the International Physical Activity Questionnaire, which estimates the total physical activity in MET-min/week, time spent sitting and classifies subjects based on their physical activity

Adherence to capsule consumptionClinical Investigation Day 1 and Clinical Investigation Day 2

Adherence will be assessed using the capsule consumption record form.

Waist circumferenceClinical Investigation Day 1 and Clinical Investigation Day 2

Waist circumference of participants in fasting condition will be analyzed by measuring tape and reported in centimeters.

Hip circumferenceClinical Investigation Day 1 and Clinical Investigation Day 2

Hip circumference of participants in fasting condition will be analyzed by measuring tape and reported in centimeters.

Neck circumferencelinical Investigation Day 1 and Clinical Investigation Day 2

Neck circumference of participants in fasting condition will be analyzed by measuring tape and reported in centimeters.

Systolic blood pressureClinical Investigation Day 1 and Clinical Investigation Day 2

Systolic blood pressure of participants in fasting condition will be analyzed by electronic tensiometer and reported in mmHg

Diastolic blood pressureClinical Investigation Day 1 and Clinical Investigation Day 2

Diastolic blood pressure of participants in fasting condition will be analyzed by electronic tensiometer and reported in mmHg

Heart rateClinical Investigation Day 1 and Clinical Investigation Day 2

Heart rate of participants in fasting condition will be analyzed by electronic tensiometer and reported in pulses/min.

Glucose concentrationClinical Investigation Day 1 and Clinical Investigation Day 2

Blood glucose levels of participants in fasting condition will be analyzed by biochemical autoanalyzer and reported in mg/dL.

Insulin concentrationClinical Investigation Day 1 and Clinical Investigation Day 2

Blood insulin concentration will be analyzed after an overnight fast by ELISA kit.

Blood glycated hemoglobinClinical Investigation Day 1 and Clinical Investigation Day 2

Fasting blood glycated hemoglobin will be reported in percentage.

HOMA indexClinical Investigation Day 1 and Clinical Investigation Day 2

HOMA index will be calculated as follows: HOMA-IR = \[fasting glucose (mmol/L) x fasting insulin (μU/ml)\] / 22.5.

Total cholesterolClinical Investigation Day 1 and Clinical Investigation Day 2

Blood total cholesterol levels of participants in fasting condition will be analyzed by biochemical autoanalyzer and reported in mg/dL

HDL cholesterolClinical Investigation Day 1 and Clinical Investigation Day 2

Blood HDL cholesterol levels of participants in fasting condition will be analyzed by biochemical autoanalyzer and reported in mg/dL

LDL cholesterolClinical Investigation Day 1 and Clinical Investigation Day 2

LDL cholesterol levels of participants in fasting condition will be analyzed by Friedewald formula and reported in mg/dL.

Triglyceride concentrationClinical Investigation Day 1 and Clinical Investigation Day 2

Triglyceride levels of participants in fasting condition will be analyzed by biochemical autoanalyzer and reported in mg/dL.

Hemogram concentrationClinical Investigation Day 1 and Clinical Investigation Day 2

Hemogram levels of participants in fasting condition will be analyzed by biochemical autoanalyzer.

LeptineClinical Investigation Day 1 and Clinical Investigation Day 2

Blood leptine concentration will be analyzed after an overnight fast by ELISA kit.

AdiponectinClinical Investigation Day 1 and Clinical Investigation Day 2

Blood adiponectin concentration will be analyzed after an overnight fast by ELISA kit.

MCP1Clinical Investigation Day 1 and Clinical Investigation Day 2

Blood MCP1 concentration will be analyzed after an overnight fast by ELISA kit.

Tumor necrosis factor alpha (TNF-alpha)Clinical Investigation Day 1 and Clinical Investigation Day 2

Blood TNF-alpha concentration will be analyzed after an overnight fast by ELISA kit.

C Reactive protein (CRP)Clinical Investigation Day 1 and Clinical Investigation Day 2

Blood CRP concentration will be analyzed after an overnight fast by ELISA kit.

Interleukin 10 (IL10)Clinical Investigation Day 1 and Clinical Investigation Day 2

Blood IL10 concentration will be analyzed after an overnight fast by ELISA kit.

Albumin concentrationClinical Investigation Day 1 and Clinical Investigation Day 2

Albumin levels of participants in fasting condition will be analyzed in urine by biochemical autoanalyzer.

Creatinine concentrationClinical Investigation Day 1 and Clinical Investigation Day 2

Creatinine levels of participants in fasting condition will be analyzed in urine by biochemical autoanalyzer and reported in μmol/L.

Life qualityClinical Investigation Day 1 and Clinical Investigation Day 2

Life quality of participants will be evaluated by SF-36 questionnaire.

Level of hungerClinical Investigation Day 1 and Clinical Investigation Day 2

Hunger of participants will be analyzed by Hunger-Satiety Visual Analogue Scale (VAS). The minimum value of the scale is 0 mm and the maximum value is 100 mm. A reduction in hunger scale means better outcome.

Level of fullnessClinical Investigation Day 1 and Clinical Investigation Day 2

Fullness of participants will be analyzed by Hunger-Satiety Visual Analogue Scale. The minimum value of the scale is 0 mm and the maximum value 100 mm. An incrementation in fullness scale means better outcome

Level of satisfactionClinical Investigation Day 1 and Clinical Investigation Day 2

Satisfaction sensation of participants will be analyzed by Hunger-Satiety Visual Analogue Scale. The minimum value of the scale is 0 mm and the maximum value 100 mm. An incrementation in satisfaction scale means better outcome.

Want to eat something elseClinical Investigation Day 1 and Clinical Investigation Day 2

Want to eat something else sensation of participants will be analyzed by Hunger-Satiety Visual Analogue Scale. The minimum value of the scale is 0 mm and the maximum value 100 mm. A reduction in want to eat something else scale means better outcome.

ThirstClinical Investigation Day 1 and Clinical Investigation Day 2

Thirst sensation of participants will be analyzed by Hunger-Satiety Visual Analogue Scale. The minimum value of the scale is 0 mm and the maximum value 100 mm.

Blood untargeted metabolomicsClinical Investigation Day 1 and Clinical Investigation Day 2

Untargeted metabolomics will be analyzed in plasma and serum.

Urine untargeted metabolomicsClinical Investigation Day 1 and Clinical Investigation Day 2

Untargeted metabolomics will be analyzed in urine.

LipidomicClinical Investigation Day 1 and Clinical Investigation Day 2

Lipidomic will be analyzed in plasma and serum.

DepressionClinical Investigation Day 1 and Clinical Investigation Day 2

Depression will be evaluated by Beck questionnaire.

AnxietyClinical Investigation Day 1 and Clinical Investigation Day 2

Anxiety will be evaluated by Stai questionnaire.

chronotypeClinical Investigation Day 1 and Clinical Investigation Day 2

Morningness-Eveningness Questionnaire (MEQ)

Trial Locations

Locations (1)

Center for Nutrition Research

🇪🇸

Pamplona, Navarra, Spain

Center for Nutrition Research
🇪🇸Pamplona, Navarra, Spain

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