Comparing Approaches to Increasing Fruit and Vegetable Intake and Their Influence on Metabolic Health

NCT ID: NCT06628401

Last Updated: 2025-10-06

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 42 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2024-10-23
• Study Completion Date: 2025-09-05

Brief Summary

This experimental study aims to evaluate the effects of different strategies for increasing fruit and vegetable intake and to see how these interventions influence markers of health in people aged 18-65 who currently consume fewer than 2 portions of fruit and vegetables a day.

The main questions it aims to answer are:

1. How does 5-a-day advice, with and without the inclusion of fruit juice, impact fruit and vegetable intake over a four-week period?

2. What are the acceptability and perceived ease of increasing fruit and vegetable intake with and without the inclusion of fruit juice in 5-a-day recommendations?

3. What are the effects of increasing fruit and vegetable intake with and without fruit juice on markers of metabolic health?

Researchers will answer these questions by comparing results from three groups of participants. All participants will provide a pre- and post-intervention blood sample, complete various questionnaires, and follow a four-week intervention that comprises educational material and a weekly £10 voucher. Over the course of the four weeks, they will report what they ate in a day on four different days.

The groups differ in the educational materials provided and where they can spend their voucher:

• Group 1 (Control) - information on the importance of including an experimental control in research and a weekly voucher to spend at a retailer of their choice,
• Group 2 (F&V) - information on 5-a-day advice (excluding fruit juice) and a weekly voucher to spend in a supermarket on F&V, and
• Group 3 (F&V + Juice) - information on 5-a-day advice (including fruit juice) and a weekly voucher to spend in a supermarket on F&V.

Conditions

Metabolic Health; Fruit and Vegetable Intake

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: OTHER
• Blinding Strategy: NONE

Study Groups

Group 1 (Control)

Participants will be asked to maintain their habitual diet throughout the intervention. They will be provided with a brief document outlining the importance of a control group in research studies to maximise compliance. They will also receive £10/week vouchers during the intervention period and a further £60 on completion of the study to replicate voucher provision in the two intervention groups. Mimicking the voucher provision structure of the intervention groups will help to minimise participant drop out and will avoid any bias associated with differential financial remuneration between groups.

Group Type: PLACEBO_COMPARATOR

Educational information (Control)

Intervention Type: BEHAVIORAL

Information packs will be developed for participants outlining the importance of a control group in research studies to maximise compliance. Participants will receive a £10 gift voucher weekly that they can spend at selected retailers of their choosing.

Group 2 (Whole F&V)

Participants will be provided with educational material to increase their fruit and vegetable intake to meet 5-a-day guidelines via exclusive intake of whole fruits/vegetables . They will receive £10/week supermarket vouchers during the intervention period to support fruit/vegetable purchase. They will receive a further £60 on completion of the study.

Group Type: ACTIVE_COMPARATOR

Educational information (Increasing F&V intake)

Intervention Type: BEHAVIORAL

Information packs will be developed to support participants in increasing their intake of whole fruits and vegetables, excluding fruit juice. The information packs will be developed using published guidance from the UK government, expert panels, and regulatory bodies. The packs will be co-developed with the public to ensure the guidance is appropriate for its target audience. Participants will also receive a £10 supermarket voucher weekly to purchase fruit and vegetables.

Group 3 (Whole F&V + Juice)

Participants will be provided with educational material to increase fruit and vegetable intake to meet 5-a-day guidelines, with recommendations to consume one portion per day via fruit juice/smoothies. Participants will receive the same financial support as group 2.

Group Type: EXPERIMENTAL

Educational information (Increasing F&V intake + Juice)

Intervention Type: BEHAVIORAL

Information packs will be developed to support participants in increasing their intake of whole fruits and vegetables, including fruit juice. The information packs will be developed using published guidance from the UK government, expert panels, and regulatory bodies. The packs will be co-developed with the public to ensure the guidance is appropriate for its target audience. Participants will also receive a £10 supermarket voucher weekly to purchase fruit and vegetables.

Interventions

Educational information (Control)

Information packs will be developed for participants outlining the importance of a control group in research studies to maximise compliance. Participants will receive a £10 gift voucher weekly that they can spend at selected retailers of their choosing.

Intervention Type: BEHAVIORAL

Educational information (Increasing F&V intake)

Information packs will be developed to support participants in increasing their intake of whole fruits and vegetables, excluding fruit juice. The information packs will be developed using published guidance from the UK government, expert panels, and regulatory bodies. The packs will be co-developed with the public to ensure the guidance is appropriate for its target audience. Participants will also receive a £10 supermarket voucher weekly to purchase fruit and vegetables.

Intervention Type: BEHAVIORAL

Educational information (Increasing F&V intake + Juice)

Information packs will be developed to support participants in increasing their intake of whole fruits and vegetables, including fruit juice. The information packs will be developed using published guidance from the UK government, expert panels, and regulatory bodies. The packs will be co-developed with the public to ensure the guidance is appropriate for its target audience. Participants will also receive a £10 supermarket voucher weekly to purchase fruit and vegetables.

Intervention Type: BEHAVIORAL

Eligibility Criteria

Inclusion Criteria

• Aged 18 - 65 years
• Currently consuming ≤2 portions of fruit and vegetables per day

Exclusion Criteria

• Using high-dose vitamins, minerals or dietary supplements that could interfere with biomarker assessment of fruit and vegetable consumption
• Have a food sensitivity, allergy or other dietary restriction (e.g., following a weight loss diet) that would limit the ability to take part in the study
• Have a medical condition (e.g., diabetes or gastrointestinal disorders) that would limit the ability to take part in the study
• Currently pregnant or lactating

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 65 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Newcastle University

OTHER

Sponsor Role: collaborator

European Fruit Juice Association (AIJN)

UNKNOWN

Sponsor Role: collaborator

Courtney Neal

OTHER

Sponsor Role: lead

Responsible Party

Courtney Neal

Research Assistant

Responsibility Role: SPONSOR_INVESTIGATOR

Principal Investigators

Oliver M Shannon, PhD

Role: PRINCIPAL_INVESTIGATOR

Newcastle University

Anthony Watson, PhD

Role: PRINCIPAL_INVESTIGATOR

Newcastle University

Locations

Newcastle University

Newcastle upon Tyne, Tyne and Wear, United Kingdom

Countries

United Kingdom

Other Identifiers

NU-019324

Identifier Type: OTHER_GRANT

Identifier Source: secondary_id

2792/48171

Identifier Type: -

Identifier Source: org_study_id