Diet Intervention Pilot: Refining a Meal and Food Delivery Approach

This study is anticipated to enroll up to 30 participants, who will be asked to complete a total of 3 visits to Vancouver General Hospital. The study will take at least 5 weeks to complete, and participants will be asked to dedicate about 11.5 hours of their time for the entire study, including 4 phone calls. The principal investigator may request to access their health records for medication or past medical history to ensure their safe participation in the study.

Participants will receive at least weekly home delivery of foods and meals to meet the nutritional goals of the dietary intervention, which include:

1. An average daily intake of 8-10 servings of fruits and vegetables high in antioxidants.

To meet this goal, a study dietician will call participants weekly to assist in ordering fruits and vegetables of their choice that meet the needs of the study and assist them in some aspects of meal planning related to these orders. These fruits and vegetables will arrive by commercially-available grocery delivery.
2. An average daily intake of over 850 mg of omega-3 fatty acids (specifically eicosapentaenoic acid and docosahexaenoic acid, also known as EPA and DHA) from fish.

To meet these goals, the study dietician will also assist participants in ordering weekly, prepared, microwaveable meals from a meal delivery service. Participants will receive four fish meals per week, which will meet the requirements of this average daily intake; participants are not required to (nor is it necessary to) eat fish every day.

• Increased EPA, DHA, fruit, and vegetable intake (Other): Participants will receive food deliveries for approximately 4-weeks via online ordering, meal delivery, and dietician counseling.

Primary outcomes

• Feasibility: Recruitment success [Through study completion (approximately 5 weeks/participant)]: Measures of recruitment success informing feasibility will include: Ratio of # in-person screens/# telephone pre-screening Ratio of # participants enrolled/# telephone pre-screening Ratio of # participants enrolled/# in-person screens
• Feasibility: Protocol completion [Through study completion (approximately 5 weeks/participant)]: Measures of protocol completion informing feasibility will include: * participants completing visit 1 * participants completing visit 2 * participants completing visit 3

Secondary outcomes

• Feasibility: Protocol adherence (dietary change) [From initiation of diet intervention to study completion (approximately 4 weeks/participant)]: Protocol adherence informing measurable change will be evaluated as follows: % completion of 24-hour recalls (6 planned per participant) Change in within-individual reported servings of fruit and vegetables across 4-week intervention (Wilcoxon matched pairs signed rank test) Change in within-individual reported servings of fish across 4-week intervention (Wilcoxon matched pairs signed rank test) Change in within-individual reported grams of omega-3 intake across initial 2 weeks and full 4-weeks of intervention (paired sample t-test) Change in blood biomarker (omega-3, carotenoid, LDL, HDL, total cholesterol) levels across initial 2 weeks and full 4-weeks of intervention (paired sample t-test)

Other outcomes

• Acceptability of the Protocol [Through study completion (approximately 5 weeks/participant)]: Feedback provided at in-person visits 2 and 3 will be reviewed and described via qualitative interview. No formal statistical analysis is planned, and these results will be published.

Sex: All, ages: 19 Years to 40 Years, accepts healthy volunteers

Inclusion Criteria:

* Healthy: defined as no significant respiratory, cardiac, or metabolic disorders (e.g. obesity, diabetes)
* No dietary supplement use (vitamins, fish oil, etc.), or willing to stop the use of supplements for one month prior to study initiation and during the study period (if the supplement is prescribed or physician-recommended, the participant will be excluded from participation)
* No use of medications known to interact with diet composition (e.g. Coumadin)
* At the time of enrolment, consuming less than 250 mg EPA+DHA daily (<2 servings fish/week) and <5 servings of fruit/vegetables per day, assessed by dietary screeners
* Not actively participating in other studies that would provide conflict with this or the alternate study protocol

Exclusion Criteria:

* Pregnant or planning to become pregnant during the study period
* Actively attempting to lose weight
* Food allergies/intolerance or food aversion preventing adherence to the intervention diet, or unwillingness/medically unable to adjust diet in line with the intervention
* Plans to move outside of British Columbia during the study period
* Lack of access to adequate food storage or food preparation appliances

These inclusion and exclusion criteria align with the anticipated inclusion criteria for an upcoming diet and air pollution exposure study for which this pilot is informing the dietary intervention.

• Emily Brigham, MD, Principal investigator, University of British Columbia