Novel Personalised Nutrition Intervention With Tailored Behavioural Support (P-NUTS)

A Novel Personalised NUtrition Intervention With Tailored Behavioural Support to Promote Sustainable and Healthy Diets in University Students: the P-NUTS Randomised Controlled Trial

The aim of this study is to test the efficacy of a novel personalised nutrition intervention with tailored behavioural support compared to a control personalised nutrition intervention for improving adherence to sustainable and healthy dietary recommendations in young (18-30 years), healthy university students.

Study Overview

• Status: Active, not recruiting
• Conditions: Behavior Change; Dietary Behaviour; Behavior Change Interventions; Behavior And Behavior Mechanism; Sustainable Healthy Diet; Personalised Nutrition
• Intervention / Treatment: Behavioral: Personalised sustainable and healthy dietary recommendations with standardised and tailored behavioural support.; Behavioral: Personalised sustainable and healthy dietary recommendations with standardised behavioural support.

Detailed Description

Recruitment:

Participants will be recruited from the University College Dublin (UCD) PLAN'EAT Living Lab (LL) Citizen Panel (https://clinicaltrials.gov/study/NCT06939231), as well as from the wider eligible UCD university population. Eligible participants will be invited to participate in a 4-week study.

Power analysis:

The trial was powered for the group main effect in an analysis of covariance (ANCOVA) of the endpoint primary outcome variable adjusted for the baseline value of the primary outcome variable. Using G*Power 3.1 (F tests → ANCOVA: fixed effects, main effects and interactions), we set α = 0.05, power = 0.80, numerator df = 1, number of groups = 2, and number of covariates = 1. The effect size was taken from the primary outcome of the pilot trial (legume intake, g/d): partial eta squared (η²p) = 0.134, converted to Cohen's f, using the formula:

f = √η²p/(1- η²p)

where η²p = 0.134, resulting in a Cohen's f of 0.393. The power calculation indicated an estimated required total sample size of 53 participants. Allowing for 20% attrition (pilot trial attrition rate: 17%), the estimated required total sample size increased to 66 participants (n=33 per group). Pilot trial registration: https://clinicaltrials.gov/study/NCT06631469.

Randomisation:

After completion of successful screening and informed consent, participants will be randomised in a 1:1 ratio to either the control or intervention group using block randomisation stratified by sex, using randomly permuted blocks of size four within each sex group to maintain equal allocation (using the blockrand package in R). This randomisation method was chosen as it resulted in a balanced distribution of demographics and baseline dietary intake data across intervention and control groups in the pilot trial.

Intervention overview:

Each group will receive different types of personalised nutrition interventions using decision tree algorithms to support them to consume a healthier and more sustainable diet. The control group will receive a personalised dietary plan and standardised behavioural support (based on the standardised support provided in the pilot trial, which was based on previous personalised nutrition trials and usual care in dietetic practice) to meet their personalised dietary recommendations. The intervention group will receive the same intervention as the control group, with additional tailored behavioural support to help them meet their personalised dietary recommendations.

Baseline:

Participants will be asked to attend a study visit at the UCD Institute of Food and Health where they will complete baseline questionnaires (i.e., consent form, demographics, health, lifestyle, medical history, medication use, supplement use, dietary behaviour questions) and a study nutritionist-guided 24-hour dietary recall via the web-based tool, Foodbook24. Upon giving consent, the participant will also be provided with two urine collection kits (one for study baseline and endpoint) and instructed to collect their urine first thing in the morning (i.e., first-void) and bring it with them on the day of their second baseline in-person visit at the UCD Institute of Food and Health. The participant will be asked to self-complete two further dietary recalls on non-consecutive days before attending the second in-person visit (for a total of three); however, participants will be allowed to attend the second in-person visit in the case that only two 24-hour dietary recalls are completed (in total).

During the second baseline in-person visit at the UCD Institute of Food and Health, a member of the research team will measure participant anthropometrics and blood pressure, while a trained nurse will take a blood sample (if consent is given). Thereafter, the study nutritionist will deliver the intervention to participants via a diet counselling session. During this session, the study nutritionist will communicate the personalised dietary recommendations developed for the participant, providing information and support on how to achieve their recommendations, along with a resource booklet with supporting information and materials (e.g., recipes, shopping lists, etc.), while asking the participant to sign a behavioural contract, where they affirm their commitment to achieving their dietary recommendations throughout the 4-week study period. Participants will be provided with a maximum of three dietary recommendations in total, which can be any combination of the following: 1) increase legume intakes; 2) increase fruit and vegetable intakes; 3) decrease meat intakes; and 4) decrease sweet/savoury discretionary food intakes.

In addition to the above, participants in the intervention group will receive tailored behavioural support to further help them to achieve their personalised dietary recommendations. The tailored behavioural supports will be developed to overcome participants' main barriers to achieving their specific dietary recommendations towards a sustainable and healthy diet. The specific tailored interventions for participants may include: provision of foods, cooking demonstration videos, habit-building support, motivation-building support, advice to seek social support, or additional knowledge provision (depending on the participant's main barriers). The main barriers to achieving specific dietary recommendations towards a sustainable and healthy diet were identified through quantitative and qualitative data collection in young (18-30 years), healthy UCD students, as part of work conducted within the PLAN'EAT Project and the UCD PLAN'EAT Living Lab (https://clinicaltrials.gov/study/NCT06939231).

Midpoint:

All participants will be contacted by their study nutritionist via email or phone call or message at the midpoint of the study (2 weeks) to check-in on their progression and to address any queries they may have.

Endpoint:

At the end of the 4-week study, participants will complete an online diet-related questionnaire and will be asked to self-complete two 24-hour dietary recalls (via the web-based tool, Foodbook24) on non-consecutive days before attending the final in-person visit at the UCD Institute of Food and Health. However, participants will be allowed to attend the final visit in the case that only one 24-hour dietary recall is completed prior to the visit. The participant will again be instructed to collect their urine first thing in the morning (i.e., first-void) and bring it with them on the day of the final in-person visit. During the final visit, a member of the research team will re-measure participant anthropometrics and blood pressure, while a trained nurse will take a blood sample (if consent is given). Finally, the participant will complete their final study nutritionist-guided 24-hour dietary recall (via the web-based tool, Foodbook24) before leaving.

Statistical analysis plan:

Continuous outcomes will be analysed using ANCOVA (with robust (Huber-White sandwich) standard errors if model residuals are non-normal and/or heteroskedasticity is present) on an intention-to-treat principle, including the baseline variable as a covariate, via the full information maximum likelihood (FIML) method, which treats missing endpoint data as missing at random (MAR). If residual distributions deviate markedly from normality, variables will be transformed prior to use in ANCOVA. Where a group x baseline covariate interaction is detected, treatment effects will be estimated at the mean value, the mean + 1 SD value, and the mean - 1 SD value of the baseline covariate.

Sensitivity analyses for both primary and secondary estimands will be conducted per protocol, with complete cases only (i.e., ≥2 24-hour dietary recalls at endpoint), which treats missing endpoint data as missing completely at random (MCAR). Data will be analysed using ANCOVA (with robust (Huber-White sandwich) standard errors if model residuals are non-normal and/or heteroskedasticity is present) or with robust regression (via M-estimation, Huber method) if residual distributions deviate markedly from normality, including the baseline variable as a covariate. Additional sensitivity analyses for both primary and secondary estimands will be performed excluding suspected dietary under-reporters.

Exploratory analyses for continuous primary and secondary outcome measures will be conducted using linear mixed models (LMMs) across three timepoints (baseline, endpoint (4 weeks), and follow-up (8 weeks)), with fixed effects for group, time, and their interaction, and a random intercept for participants to account for within-subject correlation. The time x group interaction at follow-up (8 weeks) will be the exploratory estimand of interest for the outcome measures, and between-group post-hoc tests will be conducted where a time x group interaction is significant. Models will be estimated using Restricted Maximum Likelihood (REML) under an MAR assumption. Robust (Huber-White sandwich) standard errors will be used if model residuals are non-normal and/or heteroskedasticity is present. If residual distributions deviate markedly from normality, outcomes will be transformed prior to analysis. A per-protocol sensitivity analysis will be performed using only complete cases, which assumes missingness is MCAR. An additional sensitivity analysis will be performed excluding suspected dietary under-reporters. These data will be analysed using the same LMM specification.

Categorical/ordinal outcomes will be analysed using a cumulative link model (CLM) with a logit link, including the baseline variable as a covariate. If model convergence issues arise (e.g., due to sparse outcome categories or separation), a cumulative link mixed model (CLMM) will be fitted instead, including a random intercept for participant ID and a fixed time x group interaction to assess differential change over time.

• Study Type: Interventional
• Enrollment (Estimated): 66
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Ireland
  • Dublin, Ireland, Dublin 4
    • University College Dublin, Belfield

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Be a UCD student attending Belfield Campus.
• Be an adult between the age of 18-30 years old, and in good general health.

Exclusion Criteria:

• Do not attend UCD Belfield Campus.
• Are <18 or >30 years of age.
• Have a diagnosis of an acute or chronic medical condition that could interfere with the outcomes of the study. Such diagnoses include (but are not limited to) cardiovascular disease, diabetes mellitus, cancers (within the past 5 years), etc.
• Are pregnant, lactating or planning to become pregnant.
• Are following a medically prescribed diet.
• Are immunocompromised or have a suspected immunodeficiency.
• Have a known food allergy.

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Personalised sustainable/healthy dietary recommendations with standardised and tailored support; Intervention arm.	Behavioral: Personalised sustainable and healthy dietary recommendations with standardised and tailored behavioural support.; Participants will receive a personalised dietary plan, standardised behavioural support (based on the standardised support provided in the pilot trial (https://clinicaltrials.gov/study/NCT06631469), which was based on previous personalised nutrition trials and usual care in dietetic practice), and tailored behavioural support to help participants to meet their personalised dietary recommendations.
Active Comparator: Personalised sustainable/healthy dietary recommendations with standardised support; Control arm.	Behavioral: Personalised sustainable and healthy dietary recommendations with standardised behavioural support.; Participants will receive a personalised dietary plan and standardised behavioural support (based on the standardised support provided in the pilot trial (https://clinicaltrials.gov/study/NCT06631469), which was based on previous personalised nutrition trials and usual care in dietetic practice) to help participants to meet their personalised dietary recommendations.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Legume intake (g/d)	Legume intake (g/d) will be calculated as the mean intake across multiple days at each timepoint (i.e., baseline: mean (g/d) from 2-3 24-hour dietary recalls; endpoint: mean (g/d) from 2-3 24-hour dietary recalls). If <2 recalls are available at endpoint, the endpoint's outcome is set to missing (per protocol). The primary outcome measure is endpoint legume intake (g/d). The primary estimand is the mean difference in legume intake (g/d) between groups at endpoint (4 weeks), adjusted for baseline legume intake (g/d). An exploratory analysis will be conducted to measure change in legume intake (g/d) between-groups at follow-up (8 weeks). The exploratory estimand will be the group × time interaction from a LMM at follow-up (8 weeks), and a between-group post-hoc test will be conducted where the group x time interaction is significant.	4 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total fruit and vegetable intake (g/d)	Total fruit and vegetable intake (g/d) will be calculated as the mean intake across multiple days at each timepoint (i.e., baseline: mean (g/d) from 2-3 24-hour dietary recalls; endpoint: mean (g/d) from 2-3 24-hour dietary recalls). If <2 recalls are available at endpoint, the endpoint's outcome is set to missing (per protocol). The secondary outcome measure is endpoint total fruit and vegetable intake (g/d). The secondary estimand is the mean difference in total fruit and vegetable intake (g/d) between groups at endpoint (4 weeks), adjusted for baseline total fruit and vegetable intake (g/d). An exploratory analysis will be conducted to measure change in total fruit and vegetable intake (g/d) between-groups at follow-up (8 weeks). The exploratory estimand will be the group × time interaction from a LMM at follow-up (8 weeks), and a between-group post-hoc test will be conducted where the group × time interaction is significant.	4 weeks
Total meat intake (g/d)	Total meat intake (g/d) will be calculated as the mean intake across multiple days at each timepoint (i.e., baseline: mean (g/d) from 2-3 24-hour dietary recalls; endpoint: mean (g/d) from 2-3 24-hour dietary recalls). If <2 recalls are available at endpoint, the endpoint's outcome is set to missing (per protocol). The secondary outcome measure is endpoint total meat intake (g/d). The secondary estimand is the mean difference in total meat intake (g/d) between groups at endpoint (4 weeks), adjusted for baseline total meat intake (g/d). An exploratory analysis will be conducted to measure change in total meat intake (g/d) between-groups at follow-up (8 weeks). The exploratory estimand will be the group × time interaction from a LMM at follow-up (8 weeks), and a between-group post-hoc test will be conducted where the group × time interaction is significant.	4 weeks
Total discretionary food intake (g/d)	Total discretionary food intake (g/d) will be calculated as the mean intake across multiple days at each timepoint (i.e., baseline: mean (g/d) from 2-3 24-hour dietary recalls; endpoint: mean (g/d) from 2-3 24-hour dietary recalls). If <2 recalls are available at endpoint, the endpoint's outcome is set to missing (per protocol). The secondary outcome measure is endpoint total discretionary food intake (g/d). The secondary estimand is the mean difference in total discretionary food intake (g/d) between groups at endpoint (4 weeks), adjusted for baseline total discretionary food intake (g/d). An exploratory analysis will be conducted to measure change in total discretionary food intake (g/d) between-groups at follow-up (8 weeks). The exploratory estimand will be the group × time interaction from a LMM at follow-up (8 weeks), and a between-group post-hoc test will be conducted where the group × time interaction is significant.	4 weeks
Composite dietary behaviour index (CDBI) (z-score units)	CDBI (z-score units) will be calculated as the mean of participants' dietary recommendation z-values (i.e., some combination of: legume, fruit/vegetable, total meat, and/or discretionary food z-scores) at each timepoint (i.e., baseline and endpoint). Each individual food group z-score will be calculated by mean-centring intakes (in g/d) relative to the pooled baseline mean and dividing by the pooled baseline SD of that food group. Higher endpoint CDBI scores indicate greater dietary behaviour change in the direction of participants' dietary recommendations. The secondary outcome measure is the endpoint CDBI score (z-score units). The secondary estimand is the mean difference in CDBI score (z-score units) between groups at endpoint (4 weeks), adjusted for baseline CDBI score (z-score units). An exploratory analysis will be conducted to measure change in CDBI (z-score units) between groups at follow-up. The exploratory estimand will be the LMM group x time interaction at 8 weeks f/u.	4 weeks

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Capability	Individual's self-reported capability (COM-B model component) will be calculated at baseline and endpoint based via Likert scale responses, recoded as 1-5 (i.e., from strongly disagree to strongly agree), to statements reflecting individuals' capability to achieve the dietary behavioural outcomes of interest in the current study (i.e., the primary and secondary food group outcomes). The tertiary outcome measure is the endpoint capability score. The tertiary estimand is the difference in capability score at endpoint (4 weeks), adjusted for baseline capability scores.	4 weeks
Opportunity	Individual's self-reported opportunity (COM-B model component) will be calculated at baseline and endpoint based via Likert scale responses, recoded as 1-5 (i.e., from strongly disagree to strongly agree), to statements reflecting individuals' opportunity to achieve the dietary behavioural outcomes of interest in the current study (i.e., the primary and secondary food group outcomes). The tertiary outcome measure is the endpoint opportunity score. The tertiary estimand is the difference in opportunity score at endpoint (4 weeks), adjusted for baseline opportunity scores.	4 weeks
Motivation	Individual's self-reported motivation (COM-B model component) will be calculated at baseline and endpoint based via Likert scale responses, recoded as 1-5 (i.e., from strongly disagree to strongly agree), to statements reflecting individuals' motivation to achieve the dietary behavioural outcomes of interest in the current study (i.e., the primary and secondary food group outcomes). The tertiary outcome measure is the endpoint motivation score. The tertiary estimand is the difference in motivation score at endpoint (4 weeks), adjusted for baseline motivation scores.	4 weeks
Diet-related greenhouse gas emissions (kg CO2-eq/d)	Diet-related greenhouse gas emissions (kg CO2-eq/d) will be calculated as the sum of participants' mean daily food-related greenhouse gas emissions per food product consumed (estimated via mean dietary intake across multiple days, using multiple non-consecutive 24-hour dietary recalls via the Foodbook24 software) at baseline and endpoint. The tertiary outcome measure is endpoint diet-related greenhouse gas emissions (kg CO2-eq/d). The tertiary estimand is the mean difference in endpoint diet-related greenhouse gas emissions (kg CO2-eq/d) between groups at endpoint (4 weeks), adjusted for baseline diet-related greenhouse gas emissions (kg CO2-eq/d).	4 weeks
Diet-related water footprint (L/d)	Diet-related water footprint (L/d) will be calculated as the sum of participants' mean daily food-related water footprint per food product consumed (estimated via mean dietary intake across multiple days, using multiple non-consecutive 24-hour dietary recalls via the Foodbook24 software) at baseline and endpoint. The tertiary outcome measure is endpoint diet-related water footprint (L/d). The tertiary estimand is the mean difference in endpoint diet-related water footprint (L/d) between groups at endpoint (4 weeks), adjusted for baseline diet-related water footprint (L/d).	4 weeks
Other food group intakes (g/d)	Other food group intakes (g/d) will be calculated as the mean intake across multiple days at each timepoint (i.e., baseline: mean (g/d) from 2-3 24-hour dietary recalls; endpoint: mean (g/d) from 2-3 24-hour dietary recalls). If <2 recalls are available at endpoint, the endpoint's outcome is set to missing (per protocol). The tertiary outcome measure is endpoint other food group intakes (g/d). The tertiary estimand is the mean difference in other food group intakes (g/d) between groups at endpoint (4 weeks), adjusted for baseline other food group intakes (g/d).	4 weeks
Planetary Health Diet adherence	Diet quality will be measured via adherence to the energy-adjusted Healthy Reference Diet (HRDea) score-a validated dietary index to assess adherence to the Planetary Health Diet. This index is calculated using food group and nutrient intakes, with a score ranging from 0-140, with higher scores indicating greater adherence to the Planetary Health Diet. The HRDea score will be calculated at baseline and endpoint. The tertiary outcome measure is endpoint HRDea score. The tertiary estimand is the mean difference in HRDea score between groups at endpoint (4 weeks), adjusted for baseline HRDea score.	4 weeks
Energy intake (kcal/d)	Energy intake (kcal/d) will be calculated as the mean intake across multiple days at each timepoint (i.e., baseline: mean (g/d) from 2-3 24-hour dietary recalls; endpoint: mean (g/d) from 2-3 24-hour dietary recalls). If <2 recalls are available at endpoint, the endpoint's outcome is set to missing (per protocol). The tertiary outcome measure is endpoint energy intake (kcal/d). The tertiary estimand is the mean difference in energy intake (kcal/d) between groups at endpoint (4 weeks), adjusted for baseline energy intake (kcal/d).	4 weeks
Macronutrient intakes (g/d, g/kg/d, % kcal/d)	Macronutrient intakes (g/d, g/kg/d, % kcal/d) will be calculated as the mean intake across multiple days at each timepoint (i.e., baseline: mean (g/d) from 2-3 24-hour dietary recalls; endpoint: mean (g/d) from 2-3 24-hour dietary recalls). If <2 recalls are available at endpoint, the endpoint's outcome is set to missing (per protocol). The tertiary outcome measures are endpoint macronutrient intakes (g/d, g/kg/d, % kcal/d). The tertiary estimands are the mean differences in macronutrient intakes (g/d, g/kg/d, % kcal/d) between groups at endpoint (4 weeks), adjusted for baseline macronutrient intakes (g/d, g/kg/d, % kcal/d).	4 weeks
Micronutrient intakes (mg/d, µg/d)	Micronutrient intakes (mg/d, µg/d) will be calculated as the mean intake across multiple days at each timepoint (i.e., baseline: mean (g/d) from 2-3 24-hour dietary recalls; endpoint: mean (g/d) from 2-3 24-hour dietary recalls). If <2 recalls are available at endpoint, the endpoint's outcome is set to missing (per protocol). The tertiary outcome measures are endpoint micronutrient intakes (mg/d, µg/d). The tertiary estimands are the mean differences in micronutrient intakes (mg/d, µg/d) between groups at endpoint (4 weeks), adjusted for baseline micronutrient intakes (mg/d, µg/d).	4 weeks
Body weight (kg)	Body weight (kg) will be measured using a body composition analyser (DC430MA; Tanita) at baseline and endpoint. Measurements at each timepoint will be conducted twice, with the average measurement representing the outcome value. Note: the two values to be averaged must be within <=0.1 kg of each other. Values not within limits of agreement will be discarded and measurements will be repeated until 2 valid values are obtained. The tertiary outcome measure is endpoint body weight (kg). The tertiary estimand is the mean difference in body weight (kg) between groups at endpoint (4 weeks), adjusted for baseline body weight (kg).	4 weeks
Body mass index (kg/m2)	Body mass index (kg/m2) will be computed from measured height (cm) and body weight (kg). Height (cm) and body weight (kg) will be measured using a Leicester stadiometer (Seca) and body composition analyser (DC430MA; Tanita), respectively, at baseline and endpoint. Measurements at each timepoint will be conducted twice, with the average measurement representing the outcome value. Note: the two values to be averaged must be within the following limits of agreement: <=0.1 kg for body weight; <=3 mm for height. Values not within limits of agreement will be discarded and measurements will be repeated until 2 valid values are obtained. The tertiary outcome measure is endpoint body mass index (kg/m2). The tertiary estimand is the mean difference body mass index (kg/m2) between groups at endpoint (4 weeks), adjusted for baseline body mass index (kg/m2).	4 weeks
Waist circumference (cm)	Waist circumference (cm) will be measured using an inelastic measuring tape (Seca) at baseline and endpoint. Measurement will be conducted twice, with the average measurement representing the outcome value. Note: the two values to be averaged must be within the following limits of agreement: <=1 cm for waist circumference. Values not within limits of agreement will be discarded and measurements will be repeated until 2 valid values are obtained. The tertiary outcome measure is endpoint waist circumference (cm). The tertiary estimand is the mean difference in waist circumference (cm) between groups at endpoint (4 weeks), adjusted for baseline waist circumference (cm).	4 weeks
Waist-to-hip ratio	Waist-to-hip ratio will be calculated from measured waist (cm) and hip circumference (cm) measures. Waist (cm) and hip circumference (cm) will be measured using an inelastic measuring tape (Seca). Measurements will be conducted twice, with the average measurement representing the outcome value. Note: the two values to be averaged must be within the following limits of agreement: <=1 cm for waist circumference; <=2 cm for hip circumference. Values not within limits of agreement will be discarded and measurements will be repeated until 2 valid values are obtained. The tertiary outcome measure is endpoint waist-to-hip ratio. The tertiary estimand is the mean difference in waist-to-hip ratio between groups at endpoint (4 weeks), adjusted for baseline waist-to-hip ratio.	4 weeks
Waist-to-height ratio	Waist-to-height ratio will be calculated from measured waist circumference (cm) and height (cm) measures. Waist circumference (cm) will be measured using an inelastic measuring tape (Seca). Height will be measured using a Leicester stadiometer (Seca). Measurements will be conducted twice, with the average measurement representing the outcome value. Note: the two values to be averaged must be within the following limits of agreement: <=1 cm for waist circumference; <=3 mm for height. Values not within limits of agreement will be discarded and measurements will be repeated until 2 valid values are obtained. The tertiary outcome measure is endpoint waist-to-height ratio. The tertiary estimand is the mean difference in waist-to-height ratio between groups at endpoint (4 weeks), adjusted for baseline waist-to-height ratio.	4 weeks
Blood pressure (mmHg)	Blood pressure (mmHg) will be measured after five minutes in a seated position, using an Omron M6 Comfort digital sphygmomanometer (Omron Healthcare Co. Ltd., Japan), at baseline and endpoint, with the mean of >=2 measurements used as the outcome value. The tertiary outcome measure is endpoint blood pressure (mmHg). The tertiary estimand is the mean difference in blood pressure (mmHg) between groups at endpoint (4 weeks), adjusted for baseline blood pressure (mmHg).	4 weeks
Total cholesterol (mmol/L)	Total cholesterol (mmol/L) will be measured from serum samples according to standardised clinical procedures at baseline and endpoint. The tertiary outcome measure is endpoint total cholesterol (mmol/L). The tertiary estimand is the mean difference in total cholesterol (mmol/L) between groups at endpoint (4 weeks), adjusted for baseline total cholesterol (mmol/L).	4 weeks
Low-density lipoprotein (LDL) cholesterol (mmol/L)	Low-density lipoprotein (LDL) cholesterol (mmol/L) will be measured from serum samples according to standardised clinical procedures at baseline and endpoint. The tertiary outcome measure is endpoint LDL cholesterol (mmol/L). The tertiary estimand is the mean difference in LDL cholesterol (mmol/L) between groups at endpoint (4 weeks), adjusted for baseline LDL cholesterol (mmol/L).	4 weeks
High-density lipoprotein (HDL) cholesterol (mmol/L)	High-density lipoprotein (HDL) cholesterol (mmol/L) will be measured from serum samples according to standardised clinical procedures at baseline and endpoint. The tertiary outcome measure is endpoint HDL cholesterol (mmol/L). The tertiary estimand is the mean difference in HDL cholesterol (mmol/L) between groups at endpoint (4 weeks), adjusted for baseline HDL cholesterol (mmol/L).	4 weeks
Non-high-density lipoprotein (HDL) cholesterol (mmol/L)	Non-high-density lipoprotein (HDL) cholesterol (mmol/L) will be calculated as total cholesterol (mmol/L) - HDL cholesterol (mmol/L). Total cholesterol (mmol/L) and HDL cholesterol (mmol/L) will be measured from serum samples according to standardised clinical procedures at baseline and endpoint. The tertiary outcome measure is endpoint non-HDL cholesterol (mmol/L). The tertiary estimand is the mean difference in non-HDL cholesterol (mmol/L) between groups at endpoint (4 weeks), adjusted for baseline non-HDL cholesterol (mmol/L).	4 weeks
Triglycerides (mmol/L)	Triglycerides (mmol/L) will be measured from serum samples according to standardised clinical procedures at baseline and endpoint. The tertiary outcome measure is endpoint triglycerides (mmol/L). The tertiary estimand is the mean difference in triglycerides (mmol/L) between groups at endpoint (4 weeks), adjusted for baseline triglycerides (mmol/L).	4 weeks
C-reactive protein (CRP) (mg/L)	C-reactive protein (CRP) (mg/L) will be measured from serum samples according to standardised clinical procedures at baseline and endpoint. The tertiary outcome measure is endpoint CRP (mg/L). The tertiary estimand is the mean difference in CRP (mg/L) between groups at endpoint (4 weeks), adjusted for baseline CRP (mg/L).	4 weeks
Ferritin (μg/L)	Ferritin (μg/L) will be measured from serum samples according to standardised clinical procedures at baseline and endpoint. The tertiary outcome measure is endpoint ferritin (μg/L). The tertiary estimand is the mean difference in ferritin (μg/L) between groups at endpoint (4 weeks), adjusted for baseline ferritin (μg/L).	4 weeks
Urinary biomarkers of food intake	Biomarkers of food intake will be measured from urine samples at baseline and endpoint using liquid chromatography-mass spectrometry (LC/MS) to characterise metabolomic profiles related to the dietary exposures of interest. These biomarkers are exploratory outcomes; thus, no pre-defined assay or analysis plan is reported.	4 weeks

Collaborators and Investigators

• Sponsor: University College Dublin
• Collaborators: PLAN'EAT Consortium (https://planeat-project.eu/)

Publications and helpful links

General Publications

• Davies KP, Gibney ER, Leonard UM, Lindberg L, Woodside JV, Kiely ME, Nugent AP, Arranz E, Conway MC, McCarthy SN, O'Sullivan AM. Developing and testing personalised nutrition feedback for more sustainable healthy diets: the MyPlanetDiet randomised controlled trial protocol. Eur J Nutr. 2024 Oct;63(7):2681-2696. doi: 10.1007/s00394-024-03457-0. Epub 2024 Jul 6.

Helpful Links

• Pilot trial ClinicalTrials.gov registration.
• UCD PLAN'EAT Living Lab ClinicalTrials.gov registration.
• PLAN'EAT Project website.

Study record dates

Study Major Dates

• Study Start (Actual): October 20, 2025
• Primary Completion (Estimated): May 1, 2026
• Study Completion (Estimated): May 1, 2026

Study Registration Dates

• First Submitted: December 16, 2025
• First Submitted That Met QC Criteria: February 10, 2026
• First Posted (Actual): February 18, 2026

Study Record Updates

• Last Update Posted (Actual): April 27, 2026
• Last Update Submitted That Met QC Criteria: April 24, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: Behavior change; Behaviour change; Personalised nutrition; Dietary behaviour; University students; Personalized nutrition; Legumes; Sustainable diets; Dietary behavior; Sustainable healthy diets
• Other Study ID Numbers: LS-25-69-Gibney; 101061023 (Other Grant/Funding Number: European Union Horizon Europe)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: At the beginning of the study, each participant will have a study code assigned to them. All data collected from the study will be stored using these unique study codes. A file will be set up which will be stored in a separate location to the study data. This file will contain a list which will link each participants contact details to the corresponding ID code. All stored information will be password-protected and only accessible to the research team/named researchers on the project. Anonymised data may be shared with PLAN'EAT partners, where appropriate.

Drug and device information, study documents

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