Plant Your Health RCT
Research type
Research Study
Full title
Plant Your Health: A prospective, three-arm, parallel-group, open-label, randomised, blinded-endpoint, single-centre trial comparing vegan, vegetarian, and omnivorous diets in adults with overweight or obesity.
IRAS ID
365746
Contact name
Cat Taylor
Contact email
Sponsor organisation
University of Leicester
Duration of Study in the UK
12 years, 8 months, 31 days
Research summary
Plant Your Health is a research study exploring how different diets affect health over one year. Plant-based diets such as vegetarian and vegan diets are becoming more popular and are often linked with better heart health, but it is not yet clear whether these diets directly cause improvements in cholesterol and other health measures. High-quality long-term research is limited.
We will recruit 450 adults aged 18–50 years who currently eat an omnivorous diet and have overweight or obesity. After initial checks and baseline measurements, participants will be randomly allocated to follow one of three diets for 12 months:
Vegan diet (no animal products)
Vegetarian diet (includes dairy and eggs)
Omnivorous diet (habitual diet; control group)
Participants in the vegan and vegetarian groups will receive structured dietary support, including a one-to-one consultation with a research dietitian and regular coaching throughout the year to help them follow their assigned diet.
Participants in the control group will continue their usual omnivorous diet and will receive monthly check-ins only, without any dietary advice or coaching.The main aim of the study is to determine whether a vegan or vegetarian diet leads to a greater reduction in LDL (“bad”) cholesterol over 12 months compared with a habitual omnivorous diet. We will also assess other health outcomes, such as blood pressure, blood glucose, inflammation, body composition, physical function, wellbeing, diet quality, and the environmental impact of food choices. Some participants may also be invited to take part in optional interviews to share their experiences.
The study involves visits at baseline, 6 months, and 12 months at the Leicester Diabetes Centre. The findings will help us understand whether plant-based diets are beneficial, safe, and practical, and whether they could inform future guidance for improving health and supporting sustainable lifestyles.
REC name
East Midlands - Derby Research Ethics Committee
REC reference
26/EM/0092
Date of REC Opinion
26 May 2026
REC opinion
Further Information Favourable Opinion