Overview
The primary objective of this study is to evaluate the metabolic effects of a high-fiber portfolio diet based on fermented plant-based foods compared to a corresponding non-fermented plant-based diet and a control diet (habitual diet). This will be assessed across gut microbiome profiles (high/low Prevotella), focusing on cardiometabolic risk factors, particularly inflammation.
A total of 100 men and women who meet all inclusion criteria and none of the exclusion criteria will be invited to participate. The study will employ a three-way randomized, controlled cross-over design, featuring six-week interventions separated by six-week washout periods. Participants will attend the clinic on 15 occasions, including screening visits.
Eligibility
Inclusion Criteria:
- Sign of metabolic syndrome
Waist circumference > 102 cm/88 cm M/W and at least one of the following:
- High density lipoprotein (HDL) ≤1.0 mmol/L men / HDL ≤1.3 mmol/L
- Triglycerides ≥ 1,7 mmol/L
- Blood pressure ≥130/85 mmHg
- Fasting glucose ≥5.6 mmol/L
Other inclusion criteria:
- Signed informed consent
- Willingness to consume the intervention foods
- Body mass index 25-35 kg/m2
- Hemoglobin 120-160 g/L
- Serum thyroid-stimulating hormone (S-TSH) <4 mIU/L
- Serum C-reactive protein (S-CRP) <5 mg/L
- Access to a -18⁰ C freezer
- Any medication stable for the last 14 days.
Exclusion Criteria:
- Blood donation or participation in a clinical study with blood sampling within 30 days prior to screening visit and throughout the study.
- Following any weight reduction program or having followed one during the last 6 months
- Food allergies or intolerances
- History of stomach or gastrointestinal conditions (Inflammatory bowel disease, Crohn's disease, malabsorption, colostomy, bowel resection, gastric bypass surgery, Helicobacter infection, Peptic ulcer disease, untreated celiac disease, etc.)
- Previous major gastrointestinal surgery
- Pregnant or lactating or wish to become pregnant during the period of the study.
- Unable to understand written and spoken Swedish
- Lack of suitability for participation in the trial, for any reason, as judged by the medical doctor or PI.
- Pharmacological medication with drugs known to affect the microbiota, e.g., antibiotics, within 6 months prior to baseline.
- Intake of any probiotic pills or foods enriched in probiotics within 6 months prior to baseline.
- Type I diabetes
- Small bowel bacterial overgrowth
- Diarrheal disease
- Receiving pharmacological treatment for type II diabetes (treatments based on lifestyle interventions are acceptable, as long as it is compatible with the study protocol)
- Using nicotine products on a daily basis (including chewing gum, patches, snus etc.)
- History of heart failure or heart attack (TIA) within 1 year prior to screening
- Thyroid disorder
- Planned surgery within the next eight months