Exploring how gut bacteria affect weight regain after losing weight

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This interventional study investigates the impact of antibiotic treatment on preventing weight regain in individuals who have successfully lost weight. Participants will undergo a personalized hypocaloric diet followed by a 10-day course of either antibiotics or a placebo. The study includes microbiota profiling and metabolomics assessments to understand the relationship between gut bacteria and weight maintenance. Participants will be monitored for a total of one year, with follow-up meetings to assess outcomes.

Why it matters

Who can join: the full rules

Inclusion Criteria:

* 28 \< BMI\< 40
* Age - 18-65
* Capable of working with a smartphone application

Exclusion Criteria:

* Consumption of antibiotics/probiotics/oral antifungals 2 months prior to the first day of the experiment.
* Pregnancy, fertility treatments, breastfeeding women six months prior to enrollment and during the study.
* Chronic disease, to the discretion of the study team (e.g. AIDS, Cushing syndrome, CKD, acromegaly etc.)
* Cancer and recent anticancer treatment
* Psychiatric disorders, to the discretion of the study team.
* Coagulation disorders
* IBD (inflammatory bowel diseases)
* Bariatric surgery.
* Eating disorders (Anorexia nervosa. Bulimia nervosa. Binge eating disorder, Night eating syndrome).
* Alcohol or substance abuse
* Weight loss attempts 6 months prior to the first day of the experiment - using weight loss medication.
* Drastic changes in nutritional habits six months prior to the first day of the study - to the discretion of the study team.
* Allergy to penicillin.
* Life threatening reaction after consumption of cephalosporins.
* History of CDI
* Liver disease
* History of serious unresolved diarrhea in response to antibiotic treatment to the discretion of the study doctor.

Where it's running

• Weizmann Institute of Science
  Rehovot, Israel Recruiting

Study contacts

• Principal investigator: Hila Elinav, Doctor — Hadassah Medical Organization
• Study coordinator: Eran Elinav, Professor
• Email: Eran.Elinav@weizmann.ac.il
• Phone: +97289349174

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How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.