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Denver Garden Environment and Microbiome Study Disease

A Pilot Randomized Controlled Trial of Gardening as an Intervention to Reduce Risk of Cancer and Heart

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03089151
Acronym
DGEM
Enrollment
16
Registered
2017-03-24
Start date
2016-06-02
Completion date
2017-12-30
Last updated
2021-05-07

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Chronic Disease, Diet Modification, Health Behavior, Lifestyle, Sedentary, Physical Activity, Weight Gain

Keywords

Pilot Randomized Controlled Trial, Community Garden, Health Behavior Change, Physical Activity, Diet, Obesity, Neighborhood, Microbiome, Inflammatory biomarkers

Brief summary

An interdisciplinary team with extensive garden study experience conducted a pilot randomized controlled clinical trial to see whether gardening reduced risk factors for diseases like cancer and heart disease. The pilot trial will provide preliminary data on associations between human microbiome, diet, physical activity, and social interactions and the outcomes of weight status and key inflammatory biomarkers.

Detailed description

The pilot study will lead to development of a future, large randomized controlled clinical trial, by fulfilling the following aims: Pilot Aim 1: Demonstrate feasibility of recruitment and ability to perform study procedures. Pilot Aim 2: Demonstrate the ability to measure accurately chronic disease risk factors such as diet, physical activity, weight gain, microbiome characteristics and inflammatory biomarkers. Pilot Aim 3: Provide preliminary results on the efficacy of gardens as a preventive intervention, and estimates for a detailed power analysis for the proposed subsequent larger trial. Aim 3a: Demonstrate that compared to non-gardeners, gardeners have 1) greater intake of fruits and vegetables; 2) better Healthy Eating Index (HEI); 3) lower Diet Inflammatory Index (DII); 4) reduced sedentary time and increased moderate-to-vigorous physical activity (MVPA); and reduced age-associated weight gain. Aim 3b: For gardeners and non-gardeners, sample garden soil, gut, skin, and oral microbiome at six time points from April through September to characterize and compare bacterial load, pathogenic taxa, taxonomic diversity, relative dominance, indicator taxa, and metabolomic results. Aim 3c: Demonstrate that gardening reduces inflammatory biomarkers linked to heart disease and cancer, including CRP, IL1b, IL4, IL6, IL10, and TNFa, and that the effect of gardening is mediated by diet, weight gain, physical activity and characteristics of the microbiome.

Interventions

The investigators will recruit 30 prospective gardeners who have not been gardening for the past two years and who are listed on Denver Urban Gardens (DUG) wait lists. DUG randomly assigns people on each garden wait list to available plots, using a lottery. This creates a natural randomized experiment. Participants randomized to the garden intervention will receive a standardized garden resource package, which includes the following: 1. A garden plot in a Denver Urban Garden 2. Seeds and plant starts 3. Introductory gardening workshop 4. Social events including garden-specific events and garden mentoring. The non-gardening group will remain on the DUG wait lists and will not receive these resources. Duration of the intervention is 1 year.

Sponsors

University of Colorado, Boulder
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
DOUBLE (Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes

Inclusion criteria

* Able to give informed consent in English or Spanish * Aged 18 or over * Currently on the wait list for a new garden * Not have gardened in the past 2 gardening seasons

Exclusion criteria

* Is not able to complete the study requirements in Spanish or English * Aged 17 or younger * Has gardened in the past 2 gardening seasons

Design outcomes

Primary

MeasureTime frameDescription
Change in Inflammatory biomarkers from baseline at 20 weeks20 weeksSamples include hs-CRP, TNF-alpha, IL1b, IL4, IL6, IL10
Change in taxonomic diversity from baseline at 20 weeksEvery 3-4 weeks up to 20 weeks (Week 1, Week 4, Week 7, Week 10, Week 14, Week 18)Microbiome data will be derived from 1 gut, 2 skin, and 1 oral samples
Change in relative dominance from baseline at 20 weeksEvery 3-4 weeks up to 20 weeks (Week 1, Week 4, Week 7, Week 10, Week 14, Week 18)Microbiome data will be derived from 1 gut, 2 skin, and 1 oral samples
Change in indicator taxa from baseline at 20 weeksEvery 3-4 weeks up to 20 weeks (Week 1, Week 4, Week 7, Week 10, Week 14, Week 18)Microbiome data will be derived from 1 gut, 2 skin, and 1 oral samples
Change in fruit and vegetable intake from baseline at 20 weeksMeasurements will occur during weeks 1-2 (3 random recalls) and weeks 18-20 (3 random recalls)6 24-hour diet recalls will be collected at random
Change in sedentary time behavior from baseline at 20 weeks2 measurements over 6 months, T1 (Week 1) and T6 (Week 20)Accelerometers will be adhered to thigh and collect data for 7 days
Change in bacterial load from baseline at 20 weeksEvery 3-4 weeks up to 20 weeks (Week 1, Week 4, Week 7, Week 10, Week 14, Week 18)Microbiome data will be collected six time points using 1 gut, 2 skin, and 1 oral samples
Change in moderate-to-vigorous physical activity (MVPA) from baseline at 20 weeks2 measurements over 6 months, T1 (Week 1) and T6 (Week 20)Accelerometers will be adhered to thigh and collect data for 7 days
Change in weight (kg) from baseline at 20 weeks2 measurements over 6 months, T1 (Week 1) and T6 (Week 20)Objective measurements of weight will be collected
Change in waist circumference from baseline at 20 weeks2 measurements over 6 months, T1 (Week 1) and T6 (Week 20)Objective measurement of waist circumference
Change in pathogenic taxa from baseline at 20 weeksEvery 3-4 weeks up to 20 weeks (Week 1, Week 4, Week 7, Week 10, Week 14, Week 18)Microbiome data will be derived from 1 gut, 2 skin, and 1 oral samples

Secondary

MeasureTime frameDescription
Change in blood pressure from baseline at 20 weeks20 weeks
Change in lipid profile from baseline at 20 weeks20 weeksIncluding LDL, HDL, total cholesterol, triglycerides
Change in HbA1C from baseline at 20 weeks20 weeks

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026