Mediterranean diet and socioeconomic differences in early breast cancer

Mediterranean Diet and Inequality in Early Breast Cancer: A Multicenter Randomized Clinical Trial

Phase 2 Interventional Esbjerg Hospital - University Hospital of Southern Denmark · NCT07007169

This project will test whether following a Mediterranean diet can improve the gut microbiome, quality of life, and treatment outcomes for people with early breast cancer receiving neoadjuvant or adjuvant chemotherapy, especially those with socioeconomic challenges.

Quick facts

PhasePhase 2
Study typeInterventional
Enrollment105 (estimated)
Ages18 Years and up
SexAll
SponsorEsbjerg Hospital - University Hospital of Southern Denmark Academic / other
Drugs / interventionstrastuzumab, pertuzumab, pembrolizumab, chemotherapy, immunotherapy
Locations2 sites (Esbjerg and 1 other locations)
Trial IDNCT07007169 on ClinicalTrials.gov

What this trial studies

This Phase II interdisciplinary trial combines nutrition, sociology, and oncology to see if adherence to a Mediterranean diet alters the microbiome and supports patients through (neo)adjuvant chemotherapy for stage I–III breast cancer. Participants are asked to meet daily and weekly dietary targets (minimum 30 g fiber per day and at least 30 different plant foods per week) while minimizing ultra-processed foods and avoiding probiotic supplements, with intake logged electronically. Outcomes include changes in microbiome composition, short-chain fatty acid levels, immune activity, patient-reported quality of life and empowerment, and clinical cancer outcomes. The study focuses on whether benefits are greater among patients with unfavorable socioeconomic determinants and is conducted at hospitals in Southern Denmark.

Who should consider this trial

Good fit: Adults (≥18) with histologically confirmed unilateral stage I–III breast adenocarcinoma who are candidates for neoadjuvant or adjuvant chemotherapy, have WHO performance status 0–1, consent to study procedures, can use a smartphone or computer for food logging, and will avoid probiotic supplements during the study.

Not a fit: Patients with metastatic disease, those unable or unwilling to follow the dietary targets or to use the required electronic food diary, or those who must continue probiotic supplements are unlikely to benefit from this intervention.

Why it matters

Potential benefit: If successful, the intervention could improve gut microbiome health, quality of life, immune markers, and possibly clinical outcomes for patients undergoing (neo)adjuvant chemotherapy.

How similar studies have performed: Prior research has shown that Mediterranean-style diets can benefit general health and alter the gut microbiome, but direct evidence that this diet improves clinical treatment outcomes in early breast cancer is limited, making this approach partly supported but relatively novel in this specific setting.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Signed written informed consent approved by the Ethical Review Board.
2. Age ≥ 18
3. Histologically confirmed unilateral adenocarcinoma of the breast, stage I-III, candidates for neoadjuvant chemotherapy followed by curative surgery, or adjuvant chemotherapy after curative surgery, according to the Danish Breast Cancer Group guidelines 48. The addition of trastuzumab and pertuzumab in HER2-positive tumors, or pembrolizumab in triple-negative tumors, per Danish Breast Cancer Group guidelines 48, is allowed as an adjunct to chemotherapy.
4. Good performance status (WHO performance status 0 or 1).
5. Willingness by the patient to undergo treatment and study-related procedures according to the protocol.
6. Have a smartphone or computer to which it is possible to receive emails (for food diary; www.myfood24.org)
7. Must be willing to restrict from probiotic (living microorganisms) supplements during the study. Fermented foods are allowed.

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Exclusion Criteria:

1. Clinical or radiological signs of metastatic disease.
2. History of other malignancy within the last 5 years, except for carcinoma in situ of the cervix or non-melanoma skin cancer.
3. Previous chemotherapy for cancer or other malignant disease.
4. Major altered digestive system disorders (e.g. gastric by-pass or Crohn's disease or ulcerative colitis)
5. Unable to communicate effectively in Danish or English.

Where this trial is running

Esbjerg and 1 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Early Breast CancerMicrobiomeMediterranean DietInequality in cancerChemotherapyAdjuvantNeoadjuvantShort-chain Fatty Acids
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.