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Trial registered on ANZCTR


Registration number
ACTRN12619000972123
Ethics application status
Approved
Date submitted
25/06/2019
Date registered
9/07/2019
Date last updated
23/11/2021
Date data sharing statement initially provided
9/07/2019
Date results information initially provided
7/07/2021
Type of registration
Prospectively registered

Titles & IDs
Public title
The effects of walnuts on general well­being and mood related factors in a sample of university students.
Scientific title
The effects of walnuts on general well­being, mood and blood biomarkers of stress in a sample of university students.
Secondary ID [1] 298595 0
None
Universal Trial Number (UTN)
U1111-1235-9497
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Stress 313442 0
Mood 313443 0
Gut health 316469 0
Condition category
Condition code
Neurological 311877 311877 0 0
Studies of the normal brain and nervous system
Mental Health 311935 311935 0 0
Depression
Mental Health 311936 311936 0 0
Anxiety
Mental Health 311937 311937 0 0
Other mental health disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
For this cohort study, we will recruit 80-90 undergraduate students from UniSA through student email lists and will also promote this study through other university sources. Participants will be randomly divided into two groups. One group will be required to consume half a cup of walnuts (about 50g) per day for 16 weeks and the other group will be asked to maintain a nut-free diet during the same period. The 16-week period will cover 12 weeks of study, 2 weeks of examinations and 2 weeks after examinations. All participants will undergo 3 assessments where, at each, they will provide a blood sample, a saliva sample and a faecal sample which will be used to measure stress related biomarkers (cortisol), BDNF and the gut microbiota respectively using commercially available biochemical assays and enzyme-linked immunosorbent assays (ELISA). Faecal samples (collected by patients with a home test kit) will be sent to the Australian Genome Research Facility Ltd, Melbourne, Australia for sequencing and analyses of gut microbiota. All participants will also have their mood, sleeping habits, quality of life, physical activity, and psychological well-being assessed using the Profile of Mood States (POMS), Sleep Evaluation, Assessing Quality of Life (AQoL-8D), Active Australia Survey (AAS), Perceived Stress Scale (PSS), Mental Health Continuum – Short Form (MHC-SF), and Depression Anxiety and Stress Scale (DASS21) questionnaires. The assessments will be performed at baseline (beginning of the study period), during examinations and after examinations to investigate whether daily walnut consumption can lower stress related biomarkers and improve general well-being and mental health in university students. Changes over time between the control and intervention group will be assessed using a linear mixed effects model with treatment as a between subject factor and time as the repeated measurement.

Intervention adherence will be assessed in all participants through the use of weekly checklists which we will provide. These checklists will allow participants to indicate on which days of each week they have adhered to the intervention for the duration of the study. This will allow us to keep track of any non-compliance. Each participant's checklists will be assessed at each visit and any deviation from the intervention will be recorded and advice will be given to the participant in order to maintain intervention adherence.
Intervention code [1] 314853 0
Lifestyle
Comparator / control treatment
A control group will be asked to maintain a nut-free diet during the same 16 week period of the intervention for the treatment group.
Control group
Active

Outcomes
Primary outcome [1] 320540 0
Change in mood assessed using Profile of Mood States (POMS)
Timepoint [1] 320540 0
16 weeks post commencement of walnut intervention
Primary outcome [2] 320541 0
Change in salivary cortisol assessed by enyme-linked immuosorbant assay (ELISA).
Timepoint [2] 320541 0
16 weeks post commencement of walnut intervention
Primary outcome [3] 320542 0
Change in blood neurtrophin biomarkers (brain-derived neurotrophic factor)
Timepoint [3] 320542 0
16 weeks post commencement of walnut intervention
Secondary outcome [1] 371958 0
Change in blood inflammatory biomarkers (cytokines)
Timepoint [1] 371958 0
16 weeks post commencement of walnut intervention
Secondary outcome [2] 372170 0
Change in sleeping habits assessed using the Sleep Evaluation Questionnaire
Timepoint [2] 372170 0
16 weeks post commencement of walnut intervention
Secondary outcome [3] 372171 0
Change in quality of life assessed by the Assessing Quality of Life (AQoL-8D) questionnaire.
Timepoint [3] 372171 0
16 weeks post commencement of walnut intervention
Secondary outcome [4] 372275 0
Depression, Anxiety and Stress Scale assessed using Depression, Anxiety and Stress Scale (DASS21) (primary outcome)
Timepoint [4] 372275 0
16 weeks post commencement of walnut intervention
Secondary outcome [5] 372276 0
Stress assessed using Perceived Stress Scale (PSS) (primary outcome)
Timepoint [5] 372276 0
16 weeks post commencement of walnut intervention
Secondary outcome [6] 372277 0
Change in state of mental health assessed using Mental Health Continuum - Short Form (MHC-SF) (Primary outcome)
Timepoint [6] 372277 0
16 weeks post commencement of walnut intervention
Secondary outcome [7] 380642 0
Changes in the composition of the gut microbiota assessed using stool samples (collected by participants with a home test kit) through 16s rRNA sequencing by the Australian Genome Research Facility Ltd, Melbourne, Australia.
Timepoint [7] 380642 0
16 weeks post commencement of walnut intervention

Eligibility
Key inclusion criteria
Only undergraduate participants between 18-­35 years of age will be selected
­Both male and female participants will be selected
­Participants should be equally willing to be allocated to either of the two groups

The above key inclusion criteria was implemented following recruitment of 37 participants (first cohort) and will be applied to the second cohort.
Minimum age
18 Years
Maximum age
35 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
• Existing walnut allergy
• Consumption of fish oil (>2 capsules/day) and/or nuts (>2 serves (60g) /week)
• Use of medications for depression, anxiety or any other neurological or psychiatric conditions
• Oral or pulmonary steroid use in the past 3 months
• Night shift workers
• Pregnancy
• Antibiotic use or probiotic use in the last month (due to microbiome alterations)

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Randomisation will be done by a person independent of the trial who will not be involved in data analysis.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Participants who meet the eligibility criteria will be stratified according to gender and age and randomly allocated (by a process of minimisation) toone of two dietary groups to commence the trial.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
We have reviewed our statistical methods following the new additions to the protocol. We would like to detect at least a 25% difference in mood scores, since this is the main primary outcome measure. Based on the calculations this will require 44 participants per group, therefore we will need 88 participants to complete the study.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
SA
Recruitment postcode(s) [1] 26887 0
5000 - Adelaide

Funding & Sponsors
Funding source category [1] 303137 0
University
Name [1] 303137 0
University of South Australia Division of Health Sciences: New Research Partner Scheme
Country [1] 303137 0
Australia
Funding source category [2] 303138 0
Commercial sector/Industry
Name [2] 303138 0
California Walnuts
Country [2] 303138 0
United States of America
Primary sponsor type
Individual
Name
AsProf. Larisa Bobrovskaya
Address
University of South Australia
Division of Health Sciences
City East Campus
GPO Box 2471
Adelaide SA 5001
Australia
Country
Australia
Secondary sponsor category [1] 303135 0
University
Name [1] 303135 0
University of South Australia
Address [1] 303135 0
University of South Australia
Division of Health Sciences
City East Campus
GPO Box 2471
Adelaide SA 5001
Australia
Country [1] 303135 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 303686 0
University of South Australia Human Research Ethics Committee
Ethics committee address [1] 303686 0
University of South Australia
Division of Health Sciences
City East Campus
GPO Box 2471
Adelaide SA 5001
Australia
Ethics committee country [1] 303686 0
Australia
Date submitted for ethics approval [1] 303686 0
21/05/2019
Approval date [1] 303686 0
03/07/2019
Ethics approval number [1] 303686 0
202269

Summary
Brief summary
Recent research has revealed concerning rates of anxiety, depression, sleep disorders and other mental health issues among university students. For these students, successful engagement in student life and learning activities can be significantly disrupted by fluctuations in thinking, concentration and mood, leading to low academic performance and difficulties in building social connections with their peers. Furthermore, chronic stress can lead to the disturbances in immune, neuroendocrine and neurotrophin systems.

Walnuts contain several neuro-protective compounds like vitamin E, folate, melatonin, antioxidants and omega-3 fatty acids and some studies have shown their beneficial effects on mental health in humans.

Therefore, the purpose of this study is to investigate whether daily walnut consumption can lower stress related biomarkers and improve mental health and general well-being in university students.

We hypothesize that daily consumption of walnuts by university students may relieve stress-related mood disturbances and improve their general well-being during stressful periods of study. This will be the first study to investigate the effects of walnuts on mental health and biochemical markers in young adults attending university. If walnuts have a positive effect, they could be recommended as a nutritional healthy supplement to alleviate stress related mood disturbances and improve quality of life in young adults attending university.

Participants will be randomly divided into two groups. One group will be required to consume 56g of walnuts per day for 16 weeks and the other group will be asked to maintain a nut-free diet during the same period.
Changes in mood, sleeping habits, quality of life, and psychological well-being will be clinically assessed in each participant at baseline, during examination preparation and after examinations (overall, 3 assessments).
All participants will also be asked to provide small blood and saliva samples, which will be used to measure changes in stress biomarkers over the 16-week period.

Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 94490 0
Mr Mauritz Herselman
Address 94490 0
University of South Australia
Division of Health Sciences
City East Campus
GPO Box 2471
Adelaide SA 5001
Australia
Country 94490 0
Australia
Phone 94490 0
+61 8 830 21218
Fax 94490 0
Email 94490 0
hermf001@mymail.unisa.edu.au
Contact person for public queries
Name 94491 0
A/Prof Larisa Bobrovskaya
Address 94491 0
University of South Australia
Division of Health Sciences
City East Campus
GPO Box 2471
Adelaide SA 5001
Australia
Country 94491 0
Australia
Phone 94491 0
+61 8 830 27607
Fax 94491 0
Email 94491 0
larisa.bobrovskaya@unisa.edu.au
Contact person for scientific queries
Name 94492 0
A/Prof Larisa Bobrovskaya
Address 94492 0
University of South Australia
Division of Health Sciences
City East Campus
GPO Box 2471
Adelaide SA 5001
Australia
Country 94492 0
Australia
Phone 94492 0
+61 8 830 27607
Fax 94492 0
Email 94492 0
larisa.bobrovskaya@unisa.edu.au

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment


What supporting documents are/will be available?

No Supporting Document Provided


Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
SourceTitleYear of PublicationDOI
EmbaseThe Effects of Walnuts and Academic Stress on Mental Health, General Well-Being and the Gut Microbiota in a Sample of University Students: A Randomised Clinical Trial.2022https://dx.doi.org/10.3390/nu14224776
N.B. These documents automatically identified may not have been verified by the study sponsor.