A longitudinal study to determine the effect of gene-based personalised diet and physical activity advice on adiposity indices in university students.

The study uses a randomised controlled design; data for all variables (participant characteristics, height, weight, body mass index (BMI), waist circumference (WC), body fat percentage (BF%), healthy eating motivation, dietary intake and physical activity) will be collected initially from participants at St Mary's University during September and October 2019. Participants will be genotyped, stratified randomisation (based on genotype and BMI) will be used to allocate participants to three different groups (1. Control: no advice, 2. Non genetic personalised advice: dietary and physical activity advice based on reported dietary intake and physical activity 3. Genotype- based personalised advice: dietary and physical activity advice based on genotype, reported dietary intake and physical activity. Following allocation to groups participants in groups 2 and 3 will receive appropriate dietary and physical activity advice via email (appendix a) and all participants will complete the healthy eating motivation questionnaire for a second time. In April/May 2020 follow up variables (smoking status, weight, BMI, WC, BF%, healthy eating motivation, dietary intake and physical activity) will be measured again. These follow up variables will be measured every September and April/May until September 2022. After each follow up participants in groups 2 and 3 will be resent their dietary and physical activity advice and updated information based on their reported dietary intake and physical activity.

Inclusion Criteria:

• Age 18-25 years

Exclusion Criteria:

• Pregnancy and lactation
• Chronic disease
• A history of disordered eating and following a restricted diet.