A Boost of Health: Effectiveness of a Personalized Communication Intervention to Increase Daily Fruit and Vegetable Intake

A Boost of Health: Effectiveness of a Personalized Communication Intervention Aimed at Increasing Daily Fruit and Vegetable Portions - A Study Within the PNRR 10 ON Foods Partnership

This study aims to evaluate the efficacy of a healthy diet promotion intervention focused on increasing fruit and vegetable consumption. The intervention is delivered via mobile application in a sample drawn from the healthy adult population.

Study Overview

• Status: Completed
• Conditions: Interactive Condition (HAPA-I: Group 1); Non-interactive Condition (HAPA-NI: Group 2); Non-communication Condition (No Comm: Group 3)
• Intervention / Treatment: Behavioral: Interactive communication; Behavioral: Self-monitoring; Behavioral: Non-interactive Communication

Detailed Description

The present study aims to evaluate the effectiveness of a protocol designed to increase fruit and vegetable consumption, grounded in the Health Action Process Approach (HAPA).

The protocol was delivered via the MyPocketHealth app, developed by the research team, and incorporated different communication strategies. Participants were involved in setting a goal and choosing between a personalized or a standardized goal (5 daily portions), which could be reviewed at any time. Moreover, they received either interactive (HAPA-I: group 1) or non-interactive (HAPA-NI: group 2) daily notifications promoting the target behavior through HAPA constructs for 15 days, while also monitoring their daily fruit and vegetable consumption (self-monitoring). A third group engaged solely in self-monitoring without receiving any communication (no-communication group; No comm). Goal attainment was reinforced through badge awards (rewards).

• Study Type: Interventional
• Enrollment (Actual): 403
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Italy
  • Milano
    • Milan, Milano, Italy, 20126
      • Adorni Roberta

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Individuals from the general population in good health
• Adequate level of education to understand study procedures and to use a smartphone
• Ownership and regular use of a smartphone

Exclusion Criteria:

• Medical conditions that contraindicate an increased consumption of fruit and vegetables
• Habitual consumption of five (or more) portions of fruit and vegetables per day at baseline

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Interactive condition (HAPA-I: group 1); Participants received two daily notifications. Each notification included a question about a variable from the HAPA model, and participants responded on a 5-point Likert scale. Those who scored low (1-3) received a motivational message tailored to their response. In contrast, participants who scored high (4-5) received rewarding messages. These notifications gave participants feedback on their standings within the HAPA. Moreover, participants received a daily reminder to log the portions of fruit and vegetables in a dedicated self-monitoring section of the app.	Behavioral: Interactive communication; Participants received two daily notifications. Each notification included a question about a variable from the HAPA model, and participants responded on a 5-point Likert scale. Those who scored low (1-3) received a motivational message tailored to their response. In contrast, participants who scored high (4-5) received rewarding messages. These notifications gave participants feedback on their standings within the HAPA.; Behavioral: Self-monitoring; Participants received a daily reminder to log the portions of fruit and vegetables in a dedicated self-monitoring section of the app.
Experimental: Non-interactive condition (HAPA-NI: group 2); Participants received two daily educational notifications about HAPA variables, but they did not interact with the app. The notifications for both the HAPA-I and HAPA-NI groups were identical in structure, word count, and graphic format. The only difference was the level of content customization: it was generic for the HAPA-NI group and tailored to participants' responses for the HAPA-I group. Moreover, participants received a daily reminder to log the portions of fruit and vegetables in a dedicated self-monitoring section of the app.	Behavioral: Self-monitoring; Participants received a daily reminder to log the portions of fruit and vegetables in a dedicated self-monitoring section of the app.; Behavioral: Non-interactive Communication; Participants received two daily educational notifications about HAPA variables, but they did not interact with the app. The notifications for both the HAPA-I and HAPA-NI groups were identical in structure, word count, and graphic format. The only difference was the level of content customization: it was generic for the HAPA-NI group and tailored to participants' responses for the HAPA-I group.
Experimental: Non-communication condition (No-comm: group 3); Participants did not receive HAPA-based notifications during the trial period. They received a daily reminder to log the portions of fruit and vegetables in a dedicated self-monitoring section of the app.	Behavioral: Self-monitoring; Participants received a daily reminder to log the portions of fruit and vegetables in a dedicated self-monitoring section of the app.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Daily Fruit and Vegetable Intake from Baseline	Participants self-monitored daily fruit and vegetable intake throughout the study period. Each evening, participants received a reminder and recorded the number of fruit and vegetable portions consumed that day via a dedicated app interface. At the end of the 15-day intervention, the mean daily intake was calculated for each participant. This value was then compared with baseline intake (assessed prior to the start of the intervention) to evaluate whether a statistically significant increase in daily fruit and vegetable consumption was observed.	From Day 1 to Day 15 (end of intervention)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Perceived Well-Being (WHO-5 Index)	Perceived well-being is assessed using the WHO-5 Well-Being Index, a validated self-report questionnaire that measures subjective psychological well-being. The WHO-5 consists of five items rated on a 6-point Likert scale, with higher scores indicating greater well-being. Scores are collected at baseline and at the end of the 15-day intervention. The outcome is defined as the change in WHO-5 score from baseline to post-intervention.	Baseline and Day 15 (end of intervention)

Collaborators and Investigators

• Sponsor: Marco D'Addario
• Investigators: Principal Investigator: Marco D'Addario, PhD, University of Milano Bicocca; Principal Investigator: Maria Elide Vanutelli, PhD, University of Milano Bicocca

Publications and helpful links

General Publications

• Fjeldsoe B, Neuhaus M, Winkler E, Eakin E. Systematic review of maintenance of behavior change following physical activity and dietary interventions. Health Psychol. 2011 Jan;30(1):99-109. doi: 10.1037/a0021974.
• Aune D, Giovannucci E, Boffetta P, Fadnes LT, Keum N, Norat T, Greenwood DC, Riboli E, Vatten LJ, Tonstad S. Fruit and vegetable intake and the risk of cardiovascular disease, total cancer and all-cause mortality-a systematic review and dose-response meta-analysis of prospective studies. Int J Epidemiol. 2017 Jun 1;46(3):1029-1056. doi: 10.1093/ije/dyw319.
• Schwarzer, R. (2008). Modeling health behavior change: How to predict and modify the adoption and maintenance of health behaviors. Applied Psychology: An International Review, 57(1), 1-29. https://doi.org/10.1111/j.1464-0597.2007.00325.x
• Mujcic R, J Oswald A. Evolution of Well-Being and Happiness After Increases in Consumption of Fruit and Vegetables. Am J Public Health. 2016 Aug;106(8):1504-10. doi: 10.2105/AJPH.2016.303260.
• Kamphuis CB, van Lenthe FJ, Giskes K, Brug J, Mackenbach JP. Perceived environmental determinants of physical activity and fruit and vegetable consumption among high and low socioeconomic groups in the Netherlands. Health Place. 2007 Jun;13(2):493-503. doi: 10.1016/j.healthplace.2006.05.008. Epub 2006 Jul 11.
• D'Addario M, Cappelletti ER, Sarini M, Greco A, Steca P. The TTCYB Study Protocol: A Tailored Print Message Intervention to Improve Cardiovascular Patients' Lifestyles. Int J Environ Res Public Health. 2020 Apr 23;17(8):2919. doi: 10.3390/ijerph17082919.
• Blanchflower, D. G., Oswald, A. J., & Stewart-Brown, S. (2013). Is psychological well-being linked to the consumption of fruit and vegetables? Social Indicators Research, 114(3), 785-801. https://doi.org/10.1007/s11205-012-0173-y
• Adorni R, Zanatta F, Cappelletti ER, Greco A, Steca P, D'Addario M. Effectiveness of a tailored communication intervention to improve physical activity in hypertensive patients: a twelve-month randomized controlled trial. BMC Cardiovasc Disord. 2024 Mar 5;24(1):143. doi: 10.1186/s12872-024-03786-2.

Study record dates

Study Major Dates

• Study Start (Actual): December 3, 2024
• Primary Completion (Actual): January 16, 2026
• Study Completion (Actual): January 16, 2026

Study Registration Dates

• First Submitted: May 5, 2026
• First Submitted That Met QC Criteria: May 5, 2026
• First Posted (Actual): May 12, 2026

Study Record Updates

• Last Update Posted (Actual): May 20, 2026
• Last Update Submitted That Met QC Criteria: May 18, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: mHealth; Self-monitoring; Health Action Process Approach; Healthy Diet; Rewards; Behavioral Change techniques; Behavioral Goal Setting
• Additional Relevant MeSH Terms: Investigative Techniques; Therapeutics; Clinical Laboratory Techniques; Diagnostic Techniques and Procedures; Diagnosis; Blood Chemical Analysis; Clinical Chemistry Tests; Diagnostic Techniques, Endocrine; Monitoring, Physiologic; Self-Testing; Self Care; Blood Glucose Self-Monitoring
• Other Study ID Numbers: RM-2024-882; PE00000003;CUP D93C22000890001 (Other Grant/Funding Number: Italian Ministry of University and Research funded by the European Union - NextGenerationEU)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No