Obesity
Conditions
Keywords
yogurt, dairy, calcium, weight reduction, obesity, randomized controlled trial, body composition, microbiome
Brief summary
Obesity is associated with increased morbidity and mortality, but weight reduction is difficult to achieve. In this randomized controlled trial we will include 120 obese subjects. Subjects will be allocated to one of the 3 diet types (minus 500 kcal / d): * Yoghurt diet: 500 g low-fat yogurt / d, about 1000-1100 mg calcium / d, * Milk product diet: 500 g of low-fat milk or buttermilk / d, about 1000-1100 mg calcium / d * Standard diet: 500 g soy yogurt / d, about 500 mg calcium / d Primary endpoint is the change in fat mass (baseline vs. 12 weeks), secondary endpoints are metabolic and endocrine parameters, gut microbiome, quality of life, hunger and satiety.
Interventions
DIETARY_SUPPLEMENTyogurt diet
500 g yogurt/day
DIETARY_SUPPLEMENTdairy diet
500 g non-yogurt dairy products
DIETARY_SUPPLEMENTstandard diet
500 g soya-yogurt
Sponsors
Medical University of Graz
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
Yes
Inclusion criteria
* BMI ≥30 kg/m² * Age of ≥18 and \<60 years * Written informed consent before study entry * Willingness to introduce a dietary change to lose weight
Exclusion criteria
* Serum calcium ≥2.7 mmol/l * Dislike or intolerance of dairy products, reporting adverse responses or allergy to dairy products * Pregnancy or lactating women * Having given birth in the last year or planning a pregnancy in the next 6 months * Menopause (as defined by FSH levels ≥30 IU/l) * Disorders associated with androgen excess and/or menstrual irregularities except PCOS (overt thyroid dysfunction, hyperprolactinemia, adrenal hyperplasia, androgen secreting tumors) * Malabsorption syndrome * Intake of medication influencing metabolic or endocrine parameters (insulin sensitizers, oral contraceptives, …), obesity pharmacotherapeutic agents, or calcium supplements in the last 3 months before study entry * Regular intake of calcium supplements in the last 3 months before study entry * Lifestyle changes (changes in physical activity) or weight reduction (≥10% of body weight) in the last 3 months before study entry
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| fat mass | 12 weeks | Changes in body fat mass assessed via dual-energy X-ray absorptiometry (DXA) (baseline vs. 12 weeks). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Free testosterone | 12 weeks | Free testosterone \[nmol/l\] |
| Free androgen index | 12 weeks | FAI (Free androgen index) |
| androstenedione | 12 weeks | androstenedione \[nmol/l\] |
| DHEAS | 12 weeks | dehydroepiandrosterone sulfate (DHEAS) \[µmol/L\] |
| Body composition-gynoid fat mass | 12 weeks | gynoid fat mass \[kg\] |
| Body composition-android fat mass | 12 weeks | android fat mass \[kg\] |
| AUCglucose | 12 weeks | Metabolic response during an oral glucose tolerance test (oGTT) as defined by AUCglucose |
| AUCinsulin | 12 weeks | Metabolic response during an oral glucose tolerance test (oGTT) as defined by AUCinsulin |
| HOMA-IR | 12 weeks | Insulin resistance assessed by homeostatic model assessment-insulin resistance (HOMA-IR) |
| Body weight | 12 weeks | body weight \[kg\] |
| BMI | 12 weeks | BMI \[kg/m²\] |
| waist circumference | 12 weeks | waist circumference \[cm\] |
| hip circumference | 12 weeks | hip circumference \[cm\] |
| Systolic blood pressure | 12 weeks | systolic blood pressure \[mm Hg\] |
| Diastolic blood pressure | 12 weeks | diastolic blood pressure \[mm Hg\] |
| Body composition-lean mass | 12 weeks | lean mass \[kg\] |
| Body composition-total body fat | 12 weeks | total body fat (\[%\] |
| HOMA-beta | 12 weeks | insulin sensitivity assessed by HOMA-beta |
| MATSUDA | 12 weeks | insulin sensitivity assessed by MATSUDA-index |
| QUICKI | 12 weeks | insulin sensitivity assessed by Quantitative Insulin-sensitivity Check Index (QUICKI) |
| Total cholesterol | 12 weeks | Total cholesterol \[mg/dl\] |
| LDL cholesterol | 12 weeks | LDL cholesterol \[mg/dl\] |
| HDL cholesterol | 12 weeks | HDL cholesterol \[mg/dl\] |
| Triglycerides | 12 weeks | Triglycerides \[mg/dl\] |
| HbA1c | 12 weeks | HbA1c \[mmol/mol\] |
| Total testosterone | 12 weeks | Total testosterone \[nmol/l\] |
| stool microbiome | 12 weeks | Composition of the stool microbiome Microbiome analysis will be performed through the following steps: patient collection and provision of a stool specimen, DNA isolation from the specimen, PCR reaction to amplify the selected region of the 16S rRNA gene (only present in bacteria), sequencing of the amplicons using next-generation sequencing technology, bioinformatics processing and analysis of the data using suitable software. |
| Satiety | 12 weeks | assessed via visual analogue scale \[VAS\]: Satiety, minimum score 0, maximum score 10, higher scores mean a worse outcome. |
| Food craving | 12 weeks | assessed via visual analogue scale \[VAS\]: Food craving, minimum score 0, maximum score 10, higher scores mean a worse outcome. |
| Quality of life during weight reduction | 12 weeks | Quality of life assessed via visual analogue scale \[VAS\]: How is your quality of life during weight reduction?, minimum score 0, maximum score 10, higher scores mean a better outcome. |
| Compliance | 12 weeks | assessed via visual analogue scale \[VAS\]: Compliance, minimum score 0, maximum score 10, higher scores mean a better outcome. |
Countries
Austria
Contacts
Primary ContactElisabeth Lerchbaum, MD
Outcome results
None listed