Sleep restriction has been found to dysregulate appetite regulation, leading to an increased food intake, particularly of foods high in sugar and fat. It is unclear why sleep restriction leads to increased fat and sugar intake, but emerging evidence suggests that taste preference and perception may be influenced by the lack of sleep.~Sleep restriction leads to increased preference for sucrose. However it is unclear whether sleep restriction also alters perception of sweetness, or whether it affects preference or perception of dietary fat. It is also unclear, whether any changes in sweet and fat preference and perception due to sleep restriction differ between the fasted and fed states.~This study is a randomised crossover trial where each participant will undertake two conditions (sleep restriction and normal sleep) in a randomised order. In the sleep restriction condition, participants will be asked to restrict their sleep duration to a maximum of four hours per night for two nights, and in the normal sleep group they will be asked to sleep for at least eight hours per night for two nights. There will a 4-week wash-out period between conditions. After each condition (2 nights of normal sleep or 2 nights of sleep restriction), particpants asked to arrive in a fasted state for the assessments. They will initially undertake the Control of Eating Questionnaire (COEQ) and the Leeds Food Preference Questionnaire (LFPQ). Participants will then undertake the sweet and fat taste perception and preference tests (described below). Following this, all participants will be provided with a standardized breakfast meal, and 60 minutes later, the LFPQ and taste preference and perception tests will be repeated in fed state.
The study aims is to investigate the effects of sleep restriction on sweet and fat taste perception and preference in both fasted and fed states. This is a randomised crossover trial with sleep restriction (4 hours per night for 2 nights) and normal sleep (at least 8 hours sleep for 2 nights) conditions, with a four-week washout period between conditions.