NCT07480369

Vegan Diet and Immune-Inflammatory Outcomes in Asthma and Healthy Adults

The Effect of a Vegan Diet on Inflammatory and Immune Biomarkers in Adult Patients With Asthma and in Healthy Individuals: A Randomized Controlled Trial

• Status: Not Yet Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 280 (estimated)
• Sponsor: Medical University of Gdansk · Academic / Other
• Sex: All
• Age: 18 Years – 50 Years
• Healthy volunteers: Accepted

Summary

This randomized controlled study evaluates the effects of a balanced vegan diet compared with a balanced omnivorous diet on inflammatory and immune response markers and clinical asthma parameters in healthy adults and individuals with mild to moderate asthma, aged 18 to 50. Participants will follow assigned dietary plans for 12 weeks with dietitian support delivered via digital tools.

Detailed description

This prospective, randomized, controlled study aims to evaluate the effects of a balanced vegan diet on inflammatory and immune response markers, clinical asthma parameters, and metabolic profile in healthy adults and patients with mild to moderate asthma. The study will enroll participants aged 18 to 50 years, who will be randomly assigned to either a vegan diet intervention group or a control group following an omnivorous diet for 12 weeks. Dietary interventions will be individually tailored by a clinical dietitian according to current national nutrition guidelines. To ensure safety and standardization, all participants will receive vitamin D supplementation (2000 IU/day), and participants in the vegan group will additionally receive vitamin B₁₂ supplementation (25-100 µg/day or weekly equivalent). Adherence to the diet will be monitored through weekly online consultations, 3-day food diaries, and digital tools. Assessments will be performed at baseline and after 12 weeks of intervention. Evaluated parameters will include: * Inflammatory markers: hsCRP, IL-4, IL-5, IL-13, TNF-α * Immune function markers: lymphocyte subpopulations (CD4+, CD8+, CD4+/CD8+ ratio, Treg cells by flow cytometry/ELISA) and immunoglobulins (IgE, IgA, IgG, IgG1-IgG4) * Respiratory function: fractional exhaled nitric oxide (FeNO), spirometry * Anthropometric and body composition measures: body weight, body mass index (BMI), waist circumference, waist-to-hip ratio, bioimpedance body composition analysis * Lipid profile: total cholesterol, HDL, LDL, non-HDL cholesterol, triglycerides * Asthma symptom control: Asthma Control Test (ACT) scores The planned sample size is 280 participants, distributed across four groups (n=70 per group): healthy - omnivorous diet, healthy - vegan diet, asthma - omnivorous diet, asthma - vegan diet. However, an initial pilot phase will be conducted to assess feasibility and refine study procedures before full-scale recruitment.

Conditions

• Asthma
• Dietary Intervention
• Vegan Diet

Interventions

Type	Name	Description
BEHAVIORAL	Omnivorous diet	Participants will follow an individually planned, nutritionally adequate, isocaloric omnivorous diet for 12 weeks. Diet plans will be prepared by a clinical dietitian. Adherence will be monitored 3-day food diaries, weekly remote consultations, and digital tools. Participants will receive vitamin D supplementation (2000 IU/day).
BEHAVIORAL	Vegan diet	Participants will follow an individually planned, nutritionally adequate isocaloric vegan diet for 12 weeks. Diet plans will be prepared by a clinical dietitian. Adherence will be monitored 3-day food diaries, weekly remote consultations, and digital tools. Participants will receive vitamin D supplementation (2000 IU/day) and vitamin B12 supplementation according to standard recommendations.

Timeline

• Start date: 2026-03-01
• Primary completion: 2028-12-01
• Completion: 2029-09-30
• First posted: 2026-03-18
• Last updated: 2026-03-18