The effect of mood and appetite in obese and non-obese subjects
Research type
Research Study
Full title
Modulation by mood of neuroendocrine response to gastric fatty-acid infusion and subsequent food intake in obese and normal weight subjects
IRAS ID
179616
Contact name
Qasim Aziz
Contact email
Duration of Study in the UK
2 years, 11 months, 30 days
Research summary
Evidence has shown a relationship between emotion, eating behavior and satiety hormones. Environmental cues, stress and negative mood seem to trigger behavioral eating responses that may predispose people to overeat and contribute to obesity. However the physiological, psychological and hormonal mechanisms that mediate such responses in humans are not fully understood. Previous work by the applicants, using functional Magnetic Resonance Imaging and infusion of a fat solution directly to participants’ stomach, showed an interaction between the fat infusion and experimentally induced sad emotion. Hunger scores increased during sad emotion, but this effect was reduced by fat. Also sad emotion was associated with a smaller increase in fullness sensation compared with neutral emotion. This suggests a reduced perception of fullness, which may be a mechanism underlying the consumption of larger quantities of food in sad emotional states. It is not known, however, what physiological mechanisms underlie this interaction and, in particularly, whether satiety related hormones are involved in such mediation. The aim is to investigate the effect of the interaction between a fat solution (versus saline) infusion and experimentally induced negative mood on behavioural (appetite ratings, food intake) and physiological (cortisol, oxytocin, gut peptides) responses in healthy controls and obese volunteers. As a secondary objective, to investigate the relationship between baseline psychological state and trait measures on behavioural and neuroendocrine response. Recent dietary intake will be assessed using a 2-day diet record. Psychological measures (personality, anxiety), food behaviour and appetite sensations throughout the study will be assessed by using self-report questionnaires. Emotion will be modulated using the classical music and pictures of facial expressions. Throughout the experiment, autonomic nervous system (ANS) responses will be recorded noninvasively. Small blood samples will be collected to measure hormone levels.
REC name
London - Bloomsbury Research Ethics Committee
REC reference
15/LO/1375
Date of REC Opinion
15 Sep 2015
REC opinion
Favourable Opinion