PhD Exercise Nutrition and Health Sciences

This project will investigate the genetic and environmental determinants of behavioural susceptibility to obesity in young adults. The behavioural susceptibility theory proposes that appetite-related traits such as satiety responsiveness contribute to the risk of weight gain. Supporting evidence for the theory is available in children but not adults. The new Adult Eating Behaviour Questionnaire (AEBQ), developed at UCL, psychometrically assesses eating behaviours including satiety responsiveness, food responsiveness, hunger, and slowness of eating. In children these traits have been validated against directly observed eating behaviour1 and show prospective associations with meal size, weight gain and the obesity genetic variant FTO2,3,4
ALSPAC is a world-leading resource to study the life-course determinants of eating behaviours. Bristol supervisors Johnson and Howe have funded the collection of the AEBQ in ALSPAC in the questionnaire at age 24 years (Jan-Dec 2016) and Exeter supervisor Frayling is a leader in the field of obesity genetics. This collaboration offers a unique opportunity for a student with strong quantitative skills. The student will test the genetic and environmental determinants of behavioural susceptibility to obesity in young adults for the first time using longitudinal data collected since birth. Given the range of data available the student will develop their own project direction with potential aims including:
-Assess the association of 97 genetic variants predisposing to higher BMI and adiposity5 with AEBQ sub-scales, and the extent to which AEBQ sub-scales mediate the association between the genetic risk score and adiposity
-Carry out genome-wide association studies of AEBQ sub-scales to identify novel genetic variants
-Analyse associations of life course trajectories of growth, adiposity, energy intake, physical activity and other environmental determinants (e.g. measures of mental health, sleep, socioeconomic status) with AEBQ sub-scales.
This project will not only lead to a more detailed understanding of adult eating behaviours and their mechanistic links to obesity enabling the identification of new targets for intervention, but could also underpin stratified approaches to obesity prevention by cost-effectively targeting those with a behavioural susceptibility identified using the AEBQ as a screening tool.