None listed
Conditions
Brief summary
The ZenZone Trial will test whether an eight-week dairy study is practical, safe, and acceptable for 14-year-old girls experiencing elevated depressive symptoms. Participants will be randomly assigned to consume either a yoghurt containing added BB-12, conventional yoghurt, or flavoured milk each day. The main aim is to assess recruitment, retention, adherence, completion of study activities, protocol compliance, and safety. The study will also explore changes in mood, sleep, thinking, gastrointestinal symptoms, diet, the gut microbiome, saliva biomarkers, and, for some participants, brain imaging measures. We expect the study procedures to be workable and acceptable, and will examine whether probiotic yoghurt shows more promising changes than conventional yoghurt or milk to inform a larger future trial.
Interventions
Arm 1 - Participants allocated to the intervention yoghurt arm will consume one 90 g tub of yoghurt orally once daily for eight weeks (56 days). The yoghurt contains standard yoghurt starter cultures with added Bifidobacterium animalis subsp. lactis BB-12 and provides approximately 1 × 10^9 colony-forming units of BB-12 per daily serve.
Study products will be supplied by Bega Dairy & Drinks and dispensed to participants and their parent/guardian by authorised ZenZone study staff at approximatel
Arm 1 - Participants allocated to the intervention yoghurt arm will consume one 90 g tub of yoghurt orally once daily for eight weeks (56 days). The yoghurt contains standard yoghurt starter cultures with added Bifidobacterium animalis subsp. lactis BB-12 and provides approximately 1 × 10^9 colony-forming units of BB-12 per daily serve. Study products will be supplied by Bega Dairy & Drinks and dispensed to participants and their parent/guardian by authorised ZenZone study staff at approximately Weeks 0, 3, and 6. Participants will consume the product at home and may choose between the available flavours. Participants will record each day whether they consumed all, some, or none of their allocated study product using the WeGuide application. The research dietitian will review adherence data regularly and provide supportive follow-up where missed or partial serves indicate possible adherence difficulties.
Sponsors
Deakin University
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Blinded (masking used) (Investigator)
Eligibility
Sex/Gender
All
Age
14 Years to 14 Years
Healthy volunteers
No
Inclusion criteria
Participants must meet all of the following criteria to be eligible for enrolment into the ZenZone trial: • Assigned female at birth. • Aged 14 years at the time of consent. • Experiencing elevated depressive symptoms defined as a PHQ-A score equal to or greater than 10 at the time of consent. • Willing and able to give informed consent prior to study enrolment. • Able to comply with all study procedures, including attending the study site for in-person study appointments or dairy collection (where required). • A parent or legal guardian willing and able to provide informed consent for the participant’s involvement and to comply with study procedures, including attendance at in-person study visits where required. • Access to a compatible device (smartphone, tablet, or computer) capable of downloading and using the WeGuide application, with reliable internet access.
Exclusion criteria
Participants will be excluded if they meet any of the following criteria: • Assigned male at birth. • High habitual consumption of yoghurt or similar cultured dairy products, defined as exceeding two (2) standard serves per week (approximately 400mL in total) within the four (4) weeks prior to consent, between consent and baseline assessment, or within the four (4) weeks prior to baseline assessment, to minimise baseline exposure to live-culture dairy products across all study arms. • Known or suspected allergy to dairy products (e.g., history of anaphylaxis, urticaria, angioedema, or respiratory symptoms following dairy exposure), and/or clinically significant or suspected intolerance likely to impair safe consumption of the study products, as determined by the Principal Investigator or their delegate. • Known or suspected allergy (e.g., history of anaphylaxis, urticaria, angioedema, or respiratory symptoms following dairy exposure), and/or clinically significant or suspected intolerance likely to impair safe consumption of the study products, to other components present in the interventional products as determined by the Principal Investigator or their delegate. • History of significant gastrointestinal disease or gastrointestinal surgery likely to affect digestion, absorption, or tolerance of dairy products, increase the risk of adverse events, or confound study outcomes, as determined by the Principal Investigator or their delegate. • Current or recent mental health condition requiring acute or specialised treatment (e.g., current psychotic disorder, bipolar disorder with recent manic or hypomanic episode) occurring within the four (4) weeks prior to baseline assessment, or at any time between consent and baseline assessment, or which, in the opinion of the Principal Investigator or their delegate, may pose a risk to the participant’s safety, increase the risk of adverse events, or confound study outcomes. • Acute suicidal risk, defined as active suicidal ideation with intent and/or plan, or suicidal behaviour, requiring urgent clinical intervention (e.g., emergency department presentation or inpatient admission), occurring within the four (4) weeks prior to baseline assessment or at any time between consent and baseline assessment, or identified during screening or baseline assessment. Participants identified as meeting this criterion will not be enrolled and will be referred for appropriate clinical care in accordance with the study’s risk escalation protocol. • Current diagnosis of an eating disorder, or at high risk of an eating disorder, as determined by clinical history or screening measures, due to the food-based nature of the intervention. • Neurodevelopmental, cognitive/intellectual, or communication condition that, in the opinion of the Principal Investigator or their delegate, would impair the participant’s ability to provide informed consent, comply with study procedures, or safely consume the study products, despite reasonable support from a parent or guardian. • Current participation in another interventional clinical trial that may interfere with the study intervention or outcomes. • Any known or suspected active and unstable medical condition, or a disorder that, in the opinion of the Principal Investigator of their delegate, may pose a risk to the participant’s safety or interfere with study participation or data interpretation. • Current psychological, social, or environmental circumstances that, in the opinion of the Principal Investigator or their delegate, would make participation unsafe, inappropriate, or impracticable, or would be likely to compromise adherence to the protocol or data integrity (e.g., safeguarding concerns, family instability, or inability to reliably attend assessments). • Commencement, dosage change, or discontinuation of medication for a stable ongoing condition (e.g., antidepressants) within the four (4) weeks prior to consent, or between consent and baseline assessment. • Use of antibiotics within the four (4) weeks prior to consent, or between consent and baseline assessment. • Commencement or discontinuation of probiotics, synbiotics, prebiotics, or other supplements intended to impact gut health or the gut microbiome within the four (4) weeks prior to consent, or between consent and baseline assessment.
Outcome results
None listed