Dietary Intervention Study on Food Based Dietary Guidelines for Sustainable and Healthy Lifestyles
Condition: Dietary Habits; Healthy Diet; Healthy Nutrition; Personalized Nutrition
Study type: Interventional

Summary: 
      The aim of the study is to provide proof of the effectiveness, acceptability, healthfulness
      and nutritional adequacy of dietary guidelines to reduce greenhouse gas emissions. The study
      will compare the effect of dietary advice based on 1) healthy climate-friendly dietary
      guidelines (intervention group) or 2) standard healthy dietary guidelines (control) on
      greenhouse gas emissions associated with dietary intake over 12 weeks.
    

Detailed description: 
      A randomised, parallel controlled trial will recruit n=360 healthy adults (age 18-64) across
      three research centres. After successful screening and receiving informed consent,
      participants will be randomised into the intervention or the control group for the duration
      of the 12-week trial described in detail in the text and figure below. The intervention group
      will receive dietary advice based on climate friendly eating recommendations. The control
      group will receive dietary recommendations based on Healthy Ireland's Healthy Eating
      Guidelines and Food Pyramid (FSAI, 2019).

      Prior to their first onsite visit, participants will be asked to complete a Health and
      Lifestyle questionnaire and dietary assessment. The dietary assessment will include

        1. 3 online 24-hour recalls (2 non-consecutive weekdays and 1 weekend day) (via web-based
           dietary recall tool, Foodbook24)

        2. a food frequency questionnaire (Foodbook24)

      Baseline, Visit 1 (Week 0): We will collect blood and urine samples from participants and
      record anthropometric measurements. Participants will be asked to complete a Stage of Change
      questionnaire to assess their openness to a diet change. All participants will complete a
      Food Waste Questionnaire at baseline for later comparison at endpoint. At the end of Visit 1
      participants will receive a personalised feedback report and advice from nutritionists based
      on their habitual diet.

      Week 6: Participants will be asked to complete a second dietary assessment during week 6. 3
      24-hour recalls and a food frequency questionnaire will be hosted on Foodbook24, a web-based
      dietary recall tool.

      Week 11: Before attending endpoint onsite visit, participants will complete a final dietary
      assessment. The same assessment as Pre-baseline and Week 6 will be used.

      Endpoint, Visit 2 (Week 12): At the end of 12 weeks, participants will be invited back for a
      follow-up assessment. Blood and urine samples and anthropometrics will be collected/recorded.
      Participants will complete the Stage of Change questionnaire and Food Waste questionnaire. A
      Tolerance questionnaire will be administered to see how willing participants would be to
      continue with their prescribed diet.
    

Intervention name(s): Healthy climate-friendly dietary guidelines; Healthy dietary guidelines
Intervention type(s): Behavioral; Behavioral
Intervention description(s): Personalised climate-friendly healthy dietary recommendations; Personalised healthy dietary recommendations
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Parallel randomized control trial
Masking: Single (Participant)
Primary purpose: Other
Keywords: Sustainable diets; Greenhouse gas emissions; Climate-friendly; Personalized nutrition