Optimizing an mHealth Intervention to Change Food Purchasing Behaviors for Cancer Prevention

Summary

Dietary intake is a powerful, modifiable factor that influences cancer risk. Unfortunately, most adults in the U.S. find it difficult to adhere to dietary guidelines for cancer prevention. One promising pathway for improving dietary adherence is to target grocery shopping habits, i.e., foods purchased for consumption at home. Two-thirds of daily food intake is sourced from or eaten in the home, so improving the quality of the home food environment should improve overall diet quality. When healthy foods are purchased and unhealthy foods are not, minimal self-control is needed to make healthy eating choices in the home. At the point of purchase, it is difficult to resist the temptation of palatable foods, but interventions might facilitate healthy choices by promoting dietary goal salience in real-time while grocery shopping, enhancing motivation to make and sustain changes to the diet, and increasing household support and accountability for healthy food purchasing. The proposed study will enroll adults who have low adherence to cancer prevention dietary recommendations. All participants will attend a nutrition education workshop conducted via Zoom. For 20 weeks, all participants also will receive once weekly reminders and recommendations for food purchasing via an app. The study will experimentally test four additional intervention components: location-triggered messages, coaching monitoring of food purchases, benefit of change content, and household member involvement. The preliminary aim of the study is to assess feasibility and acceptability of the intervention components. The primary aim of the study is to quantify the effect of each intervention component, individually and in combination, on dietary intake (assessed with 24-hour food recalls). The overarching goal of this project is to optimize this mHealth intervention, which can be tested in the future in a fully powered clinical trial.

Conditions

• Cancer

Interventions

BEHAVIORAL

Location-triggered notification

If participants are randomized to have this component ON, the app will send the notification when the participant's smartphone is within a 50-meter "geofence" around designated grocery stores. No more than one notification will be sent per week. Mindfulness of program goals in the moment of decision making is expected to facilitate program-consistent food purchasing behaviors. Participants assigned to have location-triggered message delivery OFF will receive their weekly "recommendations and reminders" messages at standard times throughout the week. The content of the messages will not differ according to whether this component is ON vs. OFF.

BEHAVIORAL

Reflections on benefits of change

Participants will reflect on anticipated benefits of purchasing healthy foods, consistent with motivational interviewing and self-determination theory. Message content will be personalized as follows: During the initial workshop, all participants will complete an exercise identifying benefits of healthy eating that are important to them. Message content will then be programmed to be personalized according to anticipated rewards important to that participant. Participants assigned to have this intervention component OFF will not have content about anticipated benefits of change added to any messages.

BEHAVIORAL

Coach monitoring

Coaches will monitor participant food purchases via a dashboard for viewing purchase data, and send messages designed to provide feedback and enhance supportive accountability for program goals. The messages will provide reinforcement for purchases consistent with program goals and express concern for areas in which adherence is low. Participants assigned to have this component OFF will not receive these extra messages or phone calls, and their food purchases will only be viewed by research staff for research outcome assessment purposes.

BEHAVIORAL

Household support

If participants are assigned to have household support ON, one adult in the household will receive weekly text messages designed to elicit support for changing food purchases. In addition, the index participant and household member will be invited to participate in one extra workshop session and three brief coaching calls focused on household support. If participants are assigned to have this OFF, household members will have no program involvement.

Sponsors & Collaborators

• National Cancer Institute (NCI)

  collaborator NIH

• Drexel University

  lead OTHER

Principal Investigators

• Meghan L Butryn, PhD · Drexel University

Study Design

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

SINGLE

Model

FACTORIAL

Eligibility

Min Age

18 Years

Max Age

70 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2021-06-01

Primary Completion

2022-03-29

Completion

2022-03-29

Countries

• United States

Study Locations