Exploring the Use of Genetic and Behavioural Data in Tailoring Dietary and Lifestyle Support

NCT07407556 | Active Not Recruiting

• 1 other identifier: SMU_ETHICS_2025-26_195
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

Personalised nutrition approaches typically rely on static information such as health status, lifestyle and genetic data. However, adherence often remains low because daily behaviours are influenced by psychological states, motivation and real-time barriers. There is growing interest in whether integrating behavioural signals and timely prompts could strengthen engagement. The purpose of this study is to explore whether incorporating psychological adaptation and just-in-time behavioural prompts leads to better adherence to a personalised nutrition programme compared with commonly used personalised approach (combining health, lifestyle and genetics data without psycho-behavioural adaptation). Using a six-week n-of-1 randomised trial design implemented across multiple participants, the research will also assess the feasibility of delivering this adaptive support in a free-living environment, as well as participants' engagement, acceptability and perceived usefulness. These findings will inform the development of an adaptive personalised nutrition AI agent.

Conditions

Adherence to a Personalised Nutrition Programme

Keywords

personalised nutrition; behaviour change; adherence

Outcome Measures

Primary Outcomes (1)

• Adherence

  Adherence is defined as daily completion or active attempt of the assigned lifestyle goal. Adherence is measured using a brief daily self-report item delivered via WhatsApp as part of an ecological momentary assessment. Each day, participants are asked whether they completed or actively attempted the assigned goal (Yes/No). Daily adherence is coded as a binary outcome (1 = completed, 0 = not completed). Adherence rates are calculated as the proportion of completed goal days relative to total analysable person-days and compared between personalised intervention days and static control days. An analysable person-day is defined as a day on which a goal message was successfully delivered and a corresponding adherence response was received within the response window. Days with missing responses or delivery failures are excluded from adherence analyses.

  From enrolment to the end of the 6 week intervention

Study Arms (2)

Static personalisation

ACTIVE COMPARATOR

All participants receive a fully personalised dietary and lifestyle plan based on: * baseline lifestyle and diet * health status * environmental context * genetic polymorphisms (e.g., FTO, APOA2, TCF7L2, CLOCK, TMPRSS6, FADS1/2, MTNR1B, CYP1A2, taste receptors) This ensures that both study arms receive personalised nutrition, reflecting current best practice. Participants receive: * One fixed daily behaviour goal, aligned with the weekly pillar * Personalised only according to diet, lifestyle, health status and genetics * Delivered at a pre-selected time chosen by the participant (e.g., 8:30-10:00) No adaptation is made based on: * psychological traits * daily mood/energy * anticipated or reported barriers * communication preferences (tone, length, mode) This reflects current "gold standard" personalised nutrition: personalised by biology and lifestyle, but not by psychology or dynamic states.

Behavioral: Neutral message

Fully personalised

EXPERIMENTAL

All participants receive a fully personalised dietary and lifestyle plan based on: * baseline lifestyle and diet * health status * environmental context * genetic polymorphisms (e.g., FTO, APOA2, TCF7L2, CLOCK, TMPRSS6, FADS1/2, MTNR1B, CYP1A2, taste receptors) This ensures that both study arms receive personalised nutrition, reflecting current best practice. Participants receive the same nutritional and lifestyle content, but daily goals are adapted based on: Stable Traits * Big Five personality * Health locus of control * Optimism bias * Delay discounting * Self-determination * Stress/anxiety baseline * Habit awareness * Values/motivations * Reward preferences Daily State * Morning energy rating (1-5) * Expected barriers * Context (home vs office vs weekend) Communication Preferences * tone (coachy, compassionate, factual, brief) * message length (low/medium/high) * mode (text, voice, image) Environmental and Social Context (e.g., Friday office snacks, partner-driven late dinners)

Behavioral: Psychology-tailored message

Interventions

Psychology-tailored message BEHAVIORAL

Participants receive the same nutritional and lifestyle content, but daily goals are adapted based on: Stable Traits * Big Five personality * Health locus of control * Optimism bias * Delay discounting * Self-determination * Stress/anxiety baseline * Habit awareness * Values/motivations * Reward preferences Daily State * Morning energy rating (1-5) * Expected barriers * Context (home vs office vs weekend) Communication Preferences * tone (coachy, compassionate, factual, brief) * message length (low/medium/high) * mode (text, voice, image) Environmental and Social Context (e.g., Friday office snacks, partner-driven late dinners) Daily personalisation influences: * difficulty level of the daily goal * specific behaviour change technique (BCT) chosen (e.g., action planning vs implementation intention vs coping planning) * tone, structure and timing of the message * reinforcement style The nutrition content remains identical; only HOW it is delivered changes.

Fully personalised

Neutral message BEHAVIORAL

Participants receive: * One fixed daily behaviour goal, aligned with the weekly pillar * Personalised only according to diet, lifestyle, health status and genetics * Delivered at a pre-selected time chosen by the participant (e.g., 8:30-10:00) No adaptation is made based on: * psychological traits * daily mood/energy * anticipated or reported barriers * communication preferences (tone, length, mode) This reflects current "gold standard" personalised nutrition: personalised by biology and lifestyle, but not by psychology or dynamic states.

Static personalisation

Eligibility Criteria

• Age: 18 Years - 45 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Participants must:
• Be 18-45 years old.
• Have a BMI between 18.5 and 40 kg/m² (normal weight to obesity categories).
• Own a smartphone with WhatsApp installed.
• Be willing to receive daily messages for 6 weeks.
• Be able to provide informed consent.
• Be willing to provide a cheek swab for DNA analysis.
• Have sufficient English proficiency to understand daily written instructions.
• Given that the programme focuses on the six pillars of lifestyle medicine (nutrition, physical activity, sleep, stress management, social connection, and alcohol/substance moderation), participants must be able to safely engage with light lifestyle recommendations.

You may not qualify if:

• Participants will be excluded if they:
• Have a diagnosed eating disorder or significant disordered eating symptoms.
• Are currently pregnant or breastfeeding.
• Have any medical condition requiring medically supervised dietary modification (e.g., diabetes requiring medication, kidney disease, coeliac disease).
• Are currently taking medication that significantly affects appetite, weight, or metabolism (e.g., GLP-1 agonists).
• Work night shifts
• Have severe mental health conditions (e.g., moderate-severe depression, psychosis).
• Are participating in another behaviour-change or weight-related study.
• Are unwilling to receive WhatsApp messages
• Are unwilling to receive genetic information This will be checked with PARQ questionnaire

Sponsors & Collaborators

• Alexandra King: lead
• Optimyse Nutrition LTD: collaborator

Study Sites (1)

St Mary's University

Twickenham, Middlesex, TW1 4SX, United Kingdom

Location

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Head of School Allied Health and Life Sciences

Model Details: This study is a 6-week n-of-1 micro-randomised trial (MRT) across multiple participants designed to evaluate the effect of message tailoring (psychology-tailored vs neutral) on short-term habit adherence within a fully personalised lifestyle intervention. An MRT is a within-person experimental design in which each participant is repeatedly randomised to different intervention conditions. This allows estimation of causal, moment-level effects even in small samples because each participant serves as their own control.

Study Record Dates

• First Submitted: January 23, 2026
• First Posted: February 12, 2026
• Study Start: February 13, 2026
• Primary Completion (Estimated): June 1, 2026
• Study Completion (Estimated): June 1, 2026
• Last Updated: May 1, 2026

Record last verified: 2026-02

Locations

GB (1)