NCT07234916Enrolling by invitation
Multivitamin Impact on Micronutrient Status in GLP-1 Users: A Randomized Trial
The Impact of Multivitamin Supplementation on Micronutrient Levels in GLP-1 Users: A Randomized, Double-Blind, Placebo-Controlled Trial
Source: ClinicalTrials.gov · Last updated 19 Nov 2025
Brief summary (registry, in English)
Rationale: Glucagon-Like Peptide-1 (GLP-1) receptor agonists have emerged as effective treatments for obesity and associated medical conditions. However, patients may be at risk of micronutrient deficiencies during therapy due to reduced appetite, altered gastrointestinal physiology, and weight loss. Multivitamin supplementation is commonly prescribed to mitigate these risks, but the necessity and efficacy of multivitamin use in GLP-1 users remain debatable, as some clinicians advocate for routine supplementation while others do not. Objective: To assess the differences in micronutrient levels between patients who use multivitamin supplements while on GLP-1 therapy and those who do not, to provide evidence on the necessity and benefits of supplementation. Study Design: Randomized, double-blind, placebo-controlled trial. Study Population: Adults with obesity (BMI ≥30 kg/m² or ≥27 kg/m² with obesity-associated medical problems) currently using GLP-1 receptor agonists for at least 3 months with stable dosing. Intervention: * Group A (Intervention): Multivitamin supplementation while on GLP-1 therapy * Group B (Control): Matching placebo while on GLP-1 therapy Main Study Parameters/Endpoints: The primary outcomes are the differences in serum levels of Vitamin B12, Vitamin D, and Ferritin between the multivitamin and placebo groups after 12 months of supplementation while on GLP-1 therapy. Nature and Extent of the Burden and Risks: Participants will undergo blood sampling at four timepoints: baseline (before starting GLP-1 therapy), at randomization (3 months of stable GLP-1 therapy), and at 6 and 12 months post-randomization. The risks associated with the study are minimal and primarily related to blood sampling and potential side effects of multivitamin supplementation. The burden includes time commitment for study visits and daily supplement intake.
- Status (registry)
- Enrolling by invitation
- Study type
- Interventional
- Enrollment
- 246 (estimated)
- First submitted
- 25 Apr 2025
- Start date
- 16 Dec 2025
- Primary completion date
- 16 Mar 2027
- Lead sponsor
- Erasmus Medical Center
- Diseases
- Obesity
- NCT number
- NCT07234916
What you commit to
- Study type: Interventional
- Planned participants: 246
- From 16 Dec 2025 to the primary completion date, 16 Mar 2027
- 2 sites in 1 country
- Visits and tests: ask the trial team, the registry does not list them
Built from the registry fields of ClinicalTrials.gov. It describes the study, not your situation.
Who cannot take part
Copied verbatim from ClinicalTrials.gov and grouped by topic. Only the trial team decides who can take part.
Other illness
- Known allergy or hypersensitivity to any components of the multivitamin supplement
- Active malignancy or ongoing cancer treatment
- Severe liver disease (Child-Pugh C)
- History of metabolic bariatric surgery
- Any condition that, in the investigator's opinion, would interfere with study participation or compromise patient safety
Lab values
- Severe kidney disease (eGFR \<30 mL/min/1.73m²)
Other
- Current use of other vitamin or mineral supplements
- Pregnancy or planning pregnancy during the study period
- Patients who follow a vegan diet.
- Participation in other clinical trials within the past 3 months
Who the study is looking for
- Age ≥18 to 70 years.
- Start with the use of Tirzepatide GLP-1 receptor agonists and for at least 3 months with stable dosing before randomization.
- BMI ≥30 kg/m² or ≥27 kg/m² with obesity-associated medical problems (such as type 2 diabetes, hypertension, or dyslipidemia) at the start of GLP-1 therapy
- Willing and able to provide informed consent
- Able to comply with study procedures and follow-up visits
- Own vitamins should be completely discontinued 2 weeks before the start
Age in the registry: 18 years to 70 years · Sex: All · Does not accept healthy volunteers
Sites (2)
Sites in registry order. Pick your city on the disease page to sort them by distance.
| Site | City | Country | Site status |
|---|---|---|---|
| WeightWorks Clinics Coordinator of this site? Confirm its status | Amersfoort | Netherlands | Unknown status |
| Erasmus MC Coordinator of this site? Confirm its status | Rotterdam | Netherlands | Unknown status |
This page is information, not medical advice. Discuss any trial with your doctor.