Effects of different diets on obesity and metabolic health
Complex Effects of Dietary Manipulation on Metabolic Function, Inflammation and Health
This study is testing how different diets—Mediterranean, low-carb, and very-low-fat plant-based—affect weight loss and health in people with obesity to see why some develop diabetes and others don’t.
Quick facts
| Phase | Not applicable |
|---|---|
| Study type | Interventional |
| Enrollment | 180 (estimated) |
| Ages | 18 Years to 55 Years |
| Sex | All |
| Sponsor | Washington University School of Medicine Academic / other |
| Locations | 1 site (Saint Louis, Missouri) |
| Trial ID | NCT02706262 on ClinicalTrials.gov |
What this trial studies
This research investigates how various diets impact metabolic function and inflammation in individuals with obesity. It aims to understand why some obese individuals develop related health conditions like type 2 diabetes while others do not. Participants will be assigned to one of three popular weight loss diets: Mediterranean, low-carbohydrate, or very-low-fat plant-based, to compare their effects on weight loss and metabolic health. The study will also explore the mechanisms behind individual responses to these diets.
Who should consider this trial
Good fit: Ideal candidates include metabolically abnormal obese individuals with a BMI between 30.0 and 50.0 kg/m2 and specific metabolic markers indicating insulin resistance.
Not a fit: Patients who are metabolically normal or have undergone certain types of bariatric surgery may not benefit from this study.
Why it matters
Potential benefit: If successful, this study could help identify effective dietary strategies for improving metabolic health in obese individuals.
How similar studies have performed: Other studies have shown success with dietary interventions for obesity, but this study's specific comparisons and focus on metabolic responses are relatively novel.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * Metabolically normal lean subjects must have a BMI ≥18.5 and ≤24.9 kg/m2; Obese subjects must have a BMI ≥30.0 and ≤50.0 kg/m2 * Metabolically normal lean and obese subjects must have intrahepatic triglyceride (IHTG) content ≤5%; plasma triglyceride (TG) concentration \<150 mg/dl; fasting plasma glucose concentration \<100 mg/dl, 2-hr oral glucose tolerance plasma glucose concentration \<140 mg/dl, and hemoglobin A1C ≤5.6% * Metabolically abnormal obese subjects must have intrahepatic triglyceride (IHTG) content ≥5.6%; HbA1C ≥5.7%, or fasting plasma glucose concentration ≥100 mg/dl, or 2-hr oral glucose tolerance test (OGTT) plasma glucose concentration ≥140 mg/dl. Exclusion Criteria: * Medical, surgical, or biological menopause * Previous bariatric surgery where the gastrointestinal tract is reconstructed such as Roux-en-Y, sleeve gastrectomy and biliopancreatic diversion surgeries * Laparoscopic adjustable gastric band (lab band) surgery within the last 3 years * Structured exercise ≥250 min per week (e.g., brisk walking) * Unstable weight (\>4% change during the last 2 months before entering the study) * Significant organ system dysfunction (e.g., diabetes requiring medications, severe pulmonary, kidney or cardiovascular disease) * Polycystic ovary syndrome * Cancer or cancer that has been in remission for \<5 years * Major psychiatric illness * Conditions that render subject unable to complete all testing procedures (e.g., severe ambulatory impairments, limb amputations, or metal implants that interfere with imaging procedures; coagulation disorders) * Use of medications that are known to affect the study outcome measures (e.g., steroids, non-statin lipid-lowering medications) or increase the risk of study procedures (e.g., anticoagulants) and that cannot be temporarily discontinued for this study * Use of antibiotics in last 60 days * Smoke cigarettes \> 10 cigarettes/week * Use marijuana \>2 x/week, or use of illegal drugs * Men who consume \>21 units (e.g. glass of wine or bottle of beer) of alcohol per week and women who consume \>14 units of alcohol per week * Pregnant or lactating women * Vegans, vegetarians, those with lactose intolerance and/or severe aversions/sensitivities to eggs, fish, nuts, wheat and soy, and/or any individuals with food allergies that induce an anaphylactic response * Persons who are not able to grant voluntary informed consent * Persons who are unable or unwilling to follow the study protocol or who, for any reason, the research team considers not an appropriate candidate for this study, including non-compliance with screening appointments or study visits
Where this trial is running
Saint Louis, Missouri
- Washington University School of Medicine — Saint Louis, Missouri, United States (Recruiting)
Study contacts
- Principal investigator: Samuel Klein, MD — Washington University School of Medicine
- Study coordinator: Brittney Mason
- Email: nutritionresearch@wustl.edu
- Phone: 314-273-1879
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.