Effect of Fruit Smoothie Supplementation on Psychological Distress Among People Receiving Opioid Agonist Therapy (FruktBAR)

Effect of Fruit Smoothie Supplementation on Psychological Distress Among People With Substance Use Disorders Receiving Opioid Agonist Therapy: a Randomised Controlled Trial

Background: People with substance use disorders generally have poor diets including limited intake of fruit and vegetables. Evidence shows substantial health benefits from increasing fruit and vegetable consumption on a variety of indicators and possibly also psychological distress. A pilot study has indicated that supplementation with fruit smoothie could be promising also among people receiving opioid agonist therapy (OAT) for opioid dependence. FruktBAR will compare the efficacy of fruit smoothie supplementation within the OAT clinics compared to standard treatment.

Study design: FruktBAR is a multicentre, randomised controlled trial. The trial will recruit approximately 230 patients receiving OAT in Bergen and Stavanger, Norway.

Intervention: The intervention involves daily supplementation with 250 ml fruit smoothie. The main endpoints are 16 weeks after intervention initiation. Participants will be included and followed up during and after intervention.

Study population: The target group will be patients with opioid dependence receiving OAT from involved outpatient clinics in Bergen and Stavanger.

Expected outcome: This study will inform on the relative advantages or disadvantages of a fruit supplementation in addition to the current medically and psychologically oriented treatment of people receiving opioid agonist therapy. If the supplementation is found to be safe and efficacious, it can be considered for further scale-up.

Study Overview

• Status: Completed
• Conditions: Substance-Related Disorders
• Intervention / Treatment: Dietary supplement: Fruit smoothie

Detailed Description

See below each section

• Study Type: Interventional
• Enrollment (Actual): 324
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Norway
  • Rogaland
    • Stavanger, Rogaland, Norway, 4010
      • LAR Helse Stavanger HF
  • Vestland
    • Bergen, Vestland, Norway, 5020
      • Department of Addiction Medicine, Haukeland University Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Receiving OAT from an included outpatient clinic with outpatient follow-up on weekly basis
• Having fruit and vegetable intake below 3 portions per day (assessed at screening)
• Confirming interest in participating in diet intervention (criteria specified)
• Giving informed consent

Exclusion Criteria:

• Allergies or prior anaphylactic reactions involving fruits or vegetables
• Poorly regulated diabetes type 1 or 2 (HbA1c >60 mmol/mol)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Fruit smoothie; Participants randomised to the intervention arm will receive a 250 ml fruit smoothie as diet supplement for 20 weeks in addition to the regular OAT clinic follow-up. The fruit smoothies will be marketed products including combinations of the following fruits: apple, pineapple, mango, bananas, orange, blueberries, passion fruit, coconut, lime, and blackcurrant. The participants will receive a mixture of different smoothie types with the option of removing alternatives based on preferences. Fruit smoothie products will come in plastic bottles and will be delivered directly to the participants on a weekly basis. Each participant will receive a total of seven smoothie bottles per week with an oral agreement with each participant to consume one of these per day. Delivery of fruit smoothie will generally be given in parallel with delivery of OAT medication.	Dietary supplement: Fruit smoothie; Participants randomised to the intervention arm will receive a 250 ml fruit smoothie as diet supplement for 20 weeks in addition to the regular OAT clinic follow-up. The fruit smoothies will be marketed products including combinations of the following fruits: apple, pineapple, mango, bananas, orange, blueberries, passion fruit, coconut, lime, and blackcurrant. The participants will receive a mixture of different smoothie types with the option of removing alternatives based on preferences. Fruit smoothie products will come in plastic bottles and will be delivered directly to the participants on a weekly basis. Each participant will receive a total of seven smoothie bottles per week with an oral agreement with each participant to consume one of these per day. Delivery of fruit smoothie will generally be given in parallel with delivery of OAT medication.
No Intervention: Standard; Participants randomised to standard treatment will receive regular OAT clinic follow-up without added supplementation.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Psychological distress	The primary outcome is psychological distress assessed with the Norwegian validated translation ten item version of Hopkins Symptom Checklist (SCL-10) in the mid of the intervention period 16 weeks after initiation (12-20). This will be evaluated with mean SCL-10 item score and compared between intervention and control arm.	Mid of the intervention period 16 weeks after initiation

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Physical functioning	Physical functioning assessed with 4-minute step-test measuring number of steps climbed in period	Mid of the intervention period 16 weeks after initiation
Biochemical indicator of inflammation	Biochemical indicators of inflammation measured with C-reactive protein in serum	Mid of the intervention period 16 weeks after initiation
Biochemical indicators of fruit intake	Biochemical indicators of fruit intake measured with serum carotenoids	Mid of the intervention period 16 weeks after initiation
Fatigue Symptom Scale	Changes in fatigue will be assessed with the Fatigue Symptom Scale (FSS-3, scale 0-18, higher values is worse)	Mid of the intervention period 16 weeks after initiation
Health-related quality of life	Changes in health-related quality of life will be assessed with EuroQoL EQ-5D-5L (0-100, higher is better)	Mid of the intervention period 16 weeks after initiation

Collaborators and Investigators

• Sponsor: Haukeland University Hospital
• Collaborators: University of Oslo; University of Bergen; Helse Stavanger HF; Helse Vest
• Investigators: Principal Investigator: Lars Fadnes, PhD, Haukeland University Hospital

Publications and helpful links

General Publications

• Fadnes LT, Furulund E, Druckrey-Fiskaaen KT, Madebo T, Vold JH, Olsvold M, Pierron MC, Carlsen SL, Blomhoff R, Lid TG; ATLAS4LAR Study Group. Effect of fruit smoothie supplementation on psychological distress among people with substance use disorders receiving opioid agonist therapy: protocol for a randomised controlled trial (FruktBAR). BMC Nutr. 2022 Sep 3;8(1):97. doi: 10.1186/s40795-022-00582-z.

Helpful Links

• Description of ATLAS4LAR

Study record dates

Study Major Dates

• Study Start (Actual): April 7, 2022
• Primary Completion (Actual): October 1, 2023
• Study Completion (Actual): March 15, 2025

Study Registration Dates

• First Submitted: January 24, 2022
• First Submitted That Met QC Criteria: February 7, 2022
• First Posted (Actual): February 8, 2022

Study Record Updates

• Last Update Posted (Actual): August 8, 2025
• Last Update Submitted That Met QC Criteria: August 4, 2025
• Last Verified: August 1, 2025

More Information

Terms related to this study

• Keywords: Fruit; Substance-Related Disorders; Opiate Substitution Treatment; Food Supplementations
• Additional Relevant MeSH Terms: Mental Disorders; Chemically-Induced Disorders; Substance-Related Disorders
• Other Study ID Numbers: 155386/REK-A

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
• product manufactured in and exported from the U.S.: No