Acute effect of kiwifruit on sleep quality, mood and metabolites associated with sleep in young healthy men

INTERVENTION: Participants will consume, in randomised, single‐blind fashion (cross‐over design), three different interventions, i) two fresh green kiwifruit (200g), ii) freeze‐dried green kiwifruit powder (32g) (equivalent to two whole kiwifruits) mixed with 170ml water or iii) water 170ml (control). Each participant will receive a single intakes worth of the intervention, and treatments i, ii and iii will occur on separate occasions with a seven day washout period in between. The study is an in‐home study setting. Participants will be provided with a standardised evening meal [Man Size Spaghetti and Meatballs (McCain Foods), 720 kcal] to consume four hours before their usual bed‐time. Following this, they are to consume their allocated intervention. The intervention will be provided by a researcher who is not part of the analysis of the study at the collection of a standardised meal. Before bed‐time, participants are to score their sleepiness using the Stanford Sleepiness Scale (SSS). They are then free to sleep. Upon waking the following morning, the whole morning urine sample is to be collected. From this, they are to complete the SSS, Leeds Sleep Evaluation Questionnaire (LSEQ) and a Profile of Mood States (POMS) survey. Participants will be asked to note down time intervention was consumed and will receive a text message reminder to consume intervention. The urine sample and questionnaires are to be delivered to the Institute within two hours. CONDITION: Mental Health ‐ Studies of normal psychology, cognitive function and behaviour Neurological ‐ Other neurological disorders Sleep quality;Mood state; ; Sleep quality ; Mood state PRIMARY OUTCOME: Changes in 5‐hydroxyindoleacetic acid in urine[First morning void urine samples will be used to quantify 5‐hydroxyindoleacetic acid using ELISA kit. Urine collections are at the following morning of intervention consumption.] Changes in 6‐sulfatoxymelatonin in urine[First morning void urine samples will be used to quantify 6‐sulfatoxymelatonin using ELISA kit. Urine collections are at the following morning of intervention consumption.] Changes in subjective sleep quality will be assessed using the Stanford Sleepiness Scale and the Leeds Sleep Evaluation Questionnaire and changes in objective sleep quality measurements (sleep onset latency, wake after sleep onset, total sleep time and sleep efficiency) will be measured using wrist‐worn actigraphy monitor.[This will be measured on each evening an intervention is consumed. The sleep period following the evening intervention is what will be measured.] SECONDARY OUTCOME: Changes in mood will be assessed using the Profile of Mood States (POMS) survey[Mood assessment will be conducted every morning after each intervention consumption.] Changes in urinary levels of water‐soluble vitamins (Vitamin C, thiamine; riboflavin and its vitamer FMN; the B3 vitamers: nicotinic acid, nicotinamide and nicotinuric acid, and pantothenic acid; and the B6 vitamers pyridoxal, pyridoxamine, PLP, and 4‐pyridoxic acid) using ultra‐high‐performance liquid chromatography‐tandem mass spectrometry (UHPLC‐MS/MS.[First‐morning void urine samples will be used to quantify water‐soluble vitamins mentioned above, Urine collections are at the following morning of intervention consumption.] INCLUSION CRITERIA: Healthy males Aged between 18‐35 years of age Body mass index (BMI) >18.5 or <30kg/m2 Physically active no more than 2 hours per day Good sleeper and poor sleepers ‐ Poor sleepers, defined as having Pittsburgh Sleep Quality Index (PSQI) score >5 (Buysse, Reynolds, Monk, Berman, & Kupfer, 1989), good having score <=5