IGNITE Firefighters' Health

Not Applicable

Recruiting

• Conditions: Microbiome; Immune Function; Cancer; Inflammation
• Interventions: Behavioral: Usual Firehouse Diet; Behavioral: Whole Foods Plant-Based Diet

• Registration Number: NCT06567561
• Lead Sponsor: Stanford University

Brief Summary

Investigators hope to learn about potential dietary intervention strategies (specifically a whole-food, plant-based diet) that may help lower cancer markers in firefighters.

Detailed Description

The purpose of the San Francisco (SF) Firefighter's Diet Study is to determine if a diet low in processed foods, mostly plant-based, with added fermented foods, can lower the risk of cancer in firefighters. We will assess this by randomly assigning SF firefighters to either a whole-food, plant-based diet or their usual firehouse meals. Participants will be followed for 12 weeks.

Study Timeline

• Study First Submitted: 2024-08-20
• Study First Submitted QC: 2024-08-20
• Study First Posted: 2024-08-22
• Status Verified: 2025-01
• Study Start: 2025-01-09
• Last Update Submitted: 2025-01-15
• Last Update Posted: 2025-01-17
• Primary Completion: 2025-12-30
• Study Completion: 2025-12-30

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 120

Inclusion Criteria

• Age 18+
• Active SF firefighter
• Willing to consume a plant-based diet (vegetables, fruit, whole grains, legumes, etc.)
• Willing to complete 4 clinic visits

Exclusion Criteria

• Weight < 110 lb

• BMI >= 40

• Self-reported uncontrolled hypercholesterolemia, hypertension or diabetes

• Pregnant, lactating, or planning to become pregnant during the course of the study.

• Use of any of the following drugs/supplements within the last 2 months:

  • systemic antibiotics, antifungals, antivirals, or antiparasitics (intravenous, intramuscular, or oral);
  • corticosteroids (intravenous, intramuscular, oral, nasal or inhaled);
  • cytokines;
  • methotrexate or immunosuppressive cytotoxic agents.

• Chronic, clinically significant, or unstable (unresolved, requiring ongoing changes to medical management or medication) pulmonary, cardiovascular, gastrointestinal, hepatic or renal functional abnormality, as determined by medical history, Type 1 diabetes, dialysis

• History of active cancer in the past 3 years except for squamous or basal cell carcinomas of the skin that have been medically managed by local excision

• Unstable dietary history as defined by major changes in diet during the previous month, where the subject has eliminated or significantly increased a major food group in the diet.

• Recent history of chronic excessive alcohol consumption defined as more than five 1.5-ounce servings of 80 proof distilled spirits, five 12-ounce servings of beer or five 5-ounce servings of wine per day; or > 14 drinks/week.

• Any confirmed or suspected condition/state of immunosuppression or immunodeficiency (primary or acquired) including HIV infection, multiple sclerosis, and Graves' disease.

• Surgery of the GI tract, with the exception of cholecystectomy and appendectomy, in the past five years. Any major bowel resection at any time.

• Regular/frequent use of smoking or chewing tobacco, e-cigarettes, cigars or other nicotine-containing products

• Regular use of prescription opiate pain medication

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Usual Firehouse Diet	Usual Firehouse Diet	Participants will be asked to consume their usual firehouse meals.
Whole Food Plant-Based Diet	Whole Foods Plant-Based Diet	Participants will be asked to consume and predominantly vegan, whole-foods diet, with the addition of fish, eggs, and fermented dairy.

Primary Outcome Measures

Name	Time	Method
Difference in IL-6	Baseline and 8 weeks	Difference in the 8-week change from baseline in IL-6 between the whole-food plant-based vs. usual diet groups.

Secondary Outcome Measures

Name	Time	Method
Difference in High-Density-Lipoprotein Cholesterol (HDL)	Baseline and 8 weeks	Difference in the 8-week change from baseline in High-Density-Lipoprotein Cholesterol (HDL) between the whole-food plant-based vs. usual diet groups.
Difference in Protein Carbonyl (protein oxidation)	Baseline and 8 weeks	Difference in the 8-week change from baseline in Protein Carbonyl (a measure of protein oxidation) between the whole-food plant-based vs. usual diet groups, using the enzyme-linked immunosorbent assay (ELISA).
Difference in Glyc a	Baseline and 8 weeks	Difference in the 8-week change from baseline in Glyc a between the whole-food plant-based vs. usual diet groups.
Difference in C-Reactive Protein (CRP)	Baseline and 8 weeks	Difference in the 8-week change from baseline in C-Reactive Protein (CRP) between the whole-food plant-based vs. usual diet groups.
Difference in Interleukin-10 (L-10)	Baseline and 8 weeks	Difference in the 8-week change from baseline in Interleukin-10 (IL-10) between the whole-food plant-based vs. usual diet groups.
Difference in Tumor Necrosis Factor-alpha (TNF-alpha)	Baseline and 8 weeks	Difference in the 8-week change from baseline in Tumor Necrosis Factor-alpha (TNF-alpha) between the whole-food plant-based vs. usual diet groups.
Difference in Cytokines and Inflammatory Proteins	Baseline and 8 weeks	Difference in the 8-week change from baseline in a panel of cytokines and inflammatory proteins using the NUcleic acid Linked Immuno-Sandwich Assay (NULISA™) between the whole-food plant-based vs. usual diet groups.
Difference in Calprotectin	Baseline and 8 weeks	Difference in the 8-week change from baseline in Calprotectin between the whole-food plant-based vs. usual diet groups.
Difference in 8-hydroxy-2'-deoxyguanosine (8-OH-dG)	Baseline and 8 weeks	Difference in the 8-week change from baseline in 8-hydroxy-2'-deoxyguanosine (8-OH-dG) between the whole-food plant-based vs. usual diet groups.
Difference in Lipid Peroxidation	Baseline and 8 weeks	Difference in the 8-week change from baseline in Lipid Peroxidation between the whole-food plant-based vs. usual diet groups, using the Thiobarbituric acid-reactive substance (TBARS) assay.
Difference in Fasting Glucose	Baseline and 8 weeks	Difference in the 8-week change from baseline in Fasting Glucose between the whole-food plant-based vs. usual diet groups.
Difference in Fasting Insulin	Baseline and 8 weeks	Difference in the 8-week change from baseline in Fasting Insulin between the whole-food plant-based vs. usual diet groups.
Difference in Low-Density-Lipoprotein Cholesterol (LDL)	Baseline and 8 weeks	Difference in the 8-week change from baseline in Low-Density-Lipoprotein Cholesterol (LDL) between the whole-food plant-based vs. usual diet groups.
Difference in Triglycerides (TRGs)	Baseline and 8 weeks	Difference in the 8-week change from baseline in Triglycerides (TRGs) between the whole-food plant-based vs. usual diet groups.
Difference in Telomeres	Baseline and 8 weeks	Difference in the 8-week change from baseline in Telomeres between the whole-food plant-based vs. usual diet groups.
Difference in Epigenetic Age	Baseline and 8 weeks	Difference in the 8-week change from baseline in Epigenetic Age between the whole-food plant-based vs. usual diet groups, assessed by Epigenetic Clocks.
Difference in Gut Microbiome Composition	Baseline and 8 weeks	Difference in the 8-week change from baseline in Gut Microbiome Composition between the whole-food plant-based vs. usual diet groups, assessed by Metagenomic Sequencing.
Difference in Metabolomic Profiles	Baseline and 8 weeks	Difference in the 8-week change from baseline in Gut Microbiome Composition between the whole-food plant-based vs. usual diet groups, assessed by assessed by Targeted and Untargeted Metabolomics
Difference in 4-hydroxynonenal (HNE)	Baseline and 8 weeks	Difference in the 8-week change from baseline in 4-hydroxynonenal (HNE) between the whole-food plant-based vs. usual diet groups.
Difference in body composition	Baseline and 8 weeks	Difference in the 8-week change from baseline in body composition between the whole-food plant-based vs. usual diet groups, as assessed by dual energy x-ray absorptiometry scan (DEXA) scans.
Difference in weight	Baseline and 8 weeks	Difference in the 8-week change from baseline in weight between the whole-food plant-based vs. usual diet groups.
Difference in systolic blood pressure	Baseline and 8 weeks	Difference in the 8-week change from baseline in systolic blood pressure between the whole-food plant-based vs. usual diet groups.
Difference in diastolic blood pressure	Baseline and 8 weeks	Difference in the 8-week change from baseline in diastolic blood pressure between the whole-food plant-based vs. usual diet groups.

Trial Locations

Locations (1)

Stanford University; 🇺🇸 Palo Alto, California, United States