Abstract
Background: Obesity represents a world-wide health problem. As yet, there is no gold
standard treatment. Positive psychology (PP) has been successfully applied to psychological
disorders and disturbances related to obesity. Research applying PP to address overweight and
obesity is lacking.
Aims: This research aimed to develop a positive psychological intervention (PPI) for
individuals with weight problems and assess its effectiveness on well-being and weight loss in
non-clinical populations. Further aims were to identify potential molecular genetic pathways
through which the PPI functions, and validate the intervention using OXTR gene expression as
a model system.
Method: A 6-week PPI for weight management was delivered in two pilot studies
(n=38) and a randomised controlled trial (RCT; n=20) to students and staff at an English
University. Saliva samples were collected in weekly basis during the intervention sessions and
qRT-PCR was used to analyse relative OXTR expression in the samples.
Results: Quantitative analyses of the pilot studies revealed significant increases in well
being and decreases in depression and anxiety. RCT findings revealed significant increases in
well-being and decreases in anxiety in the intervention group. Differential gene expression
analysis using a real time RT-PCR approach revealed significant increases in the OXTR gene
expression levels in response to the intervention. Bioinformatic approaches revealed a number
of genexgene interactions, elucidating potential novel molecular genetic pathways that may
affect psychological wellbeing.
Conclusions: The current PPI made an effective contribution to mental health
and overall well-being of participants in all three studies. The PPI may be able to modulate
expression of genes related to positive psychological functioning, leading to increased well
being. Finally, it is proposed that the OXTR expression levels could be used as an experimental
assay in validation of PPIs, promoting the practical legacy of PP.