The effect of a single high-fat meal and the protective effect of naturally occurring polyphenolic compounds on artery function

INTERVENTION: This study will help us assess the effect of a high‐fat meal on our blood vessels (cardiovascular health) and how naturally occurring polyphenolic compounds in plant foods could potentially affect this beneficially. This will be a single‐blinded, 3‐armed randomised crossover interventional trial in young, apparently healthy men. Participants will be screened via an online survey for eligibility with likely candidates invited for an in‐person screening session at the BASE facility (Be Active Sleep Eat) at Monash University, Notting Hill campus. At the screening visit, anthropometry, blood pressure, endothelial function via flow mediated dilation (FMD) and fasting glucose, triglycerides and cholesterol will be measured by a trained researcher. After completion of a physical activity questionnaire, a general demographics survey and a food record participants will be booked in for a testing visit. Each participant will complete arm 1 and 2 testing visits plus can opt‐in for the third arm testing visit. Arm 1: High‐Fat milkshake + control (1g fat per kilo of bodyweight) Arm 2: High‐Fat milkshake + 26 g freeze dried blueberries + 12.24g high flavanol cocoa powder (per 75 kg of bodyweight) Arm 3: Fasting All interventions will be delivered face‐to‐face on at least two separate occasions over 7.5 hours. There is a minimum 1 week washout period between the intervention sessions. For 24 hours before testing, participants will avoid strenuous exercise and consume at least 2 L of fluids. On the morning of testing, following an overnight fast from 9 pm (water is allowed) participants will present at BASE and undergo baseline measurements, participants will then either consume the high fat meal plus additives or continue to fast. All intervention fo CONDITION: Cardiovascular ‐ Normal development and function of the cardiovascular system Cardiovascular disease risk;Arterial endothelial function; ; Cardiovascular disease risk ; Arterial endothelial function Diet and Nutrition ‐ Other diet and nutrition disorders PRIMARY OUTCOME: Change in endothelial function determined by ultrasound scans of Flow‐Mediated Dilation (FMD)[Completed at the screening visit (Familiarisation). For the testing visits: postprandial time course study with measurements taken at baseline and hourly up to 6 hours after the meal. There is no one time point that is the primary time point.] INCLUSION CRITERIA: Young (More than 18 years old and less than 31 years old), apparently healthy, non‐smoking males with a BMI between 18.5 or above 27 kg/m2. SECONDARY OUTCOME: Anthropometric measurements: bodyweight in kg will be assessed using scales and height in cm will be assessed using a stadiometer and both will be used to enable calculation of body mass inde X(BMI).[Single time point at all visits] Body composition (fat mass, fat‐free mass, muscle mass and total body water) will be determined using bioelectric‐impedance analysis (515/514 SECA Medical Body Composition Analyser)[Single time point at all visits] Change in blood pressure using an automated blood pressure monitor (Omron).[Postprandial time course study with measurements taken at baseline and hourly up to 6 hours after the meal. ] Change in plasma glucose concentration, measured on an Indiko Analyser[Postprandial time course study with venous blood samples taken at baseline and then at 15 min, 30 min, 45 min, 60 min, 90 min, 120 min, 150 min, 180 min, 240 min, 300 min and 360 min after the meal ] Change in plasma insulin concentration, measured by ELISA.[Postprandial time course study with venous blood samples taken at baseline and then at 15 min, 30 min, 45 min, 60 min, 90 min, 120 min, 150 min, 180 min, 240 min, 300 min and 360 min after the meal ] Change in plasma superoxide dismutase 1 (SOD1), measured by ELISA.[Postprandial time course study with venous blood samples taken at baseline and then at 15 min, 30 min, 45 min, 60 min, 90 min, 120 min, 150 min, 180 min, 240 min, 300 min and 360 min after the meal.] Change in serum cholesterol (total, HDL and LDL) concentration, measured on an Indiko Analyser.[Postprandial time course study with venous blood samples taken at baseline and then at 15 min, 30 min, 45 min, 60 min, 90 min, 120 min, 150 min, 180 min, 240 min, 300 min and 360 min after the meal ] Change in serum high sensitivity C‐Reactive Protein (hsCRP), measured on an Indiko Analyser.[Postprandial time course study with venous blood samples taken at baseline and then at 15 min, 30 min, 45 min, 60 min, 90 min, 120 min, 150 min, 180 min, 240 min, 300 min and 360 min after the meal ] Change in serum triglyceride concentration, measured on an Indiko Analyser.[Postprandial time course study with venous blood samples taken at baseline and then at 15 min, 30 min, 45 min, 60 min, 90 min, 120 min, 150 min, 180 min, 240 min, 300 min and 360 min after the meal ] Long‐term advanced glycation end‐product (AGE) deposition in skin tissue (measurement of skin autofluorescence using an AGE Reader)[Single time point at screening visit] Myeloperoxidase (MPO) enzyme activity in serum as assessed by colorimetric assay[Postprandial time course study with venous blood samples taken at baseline and then at 15 min, 30 min, 45 min, 60 min, 90 min, 120 min, 150 min, 180 min, 240 min, 300 min and 360 min after the meal] Usual dietary intake (energy intake and macronutrient composition) as assessed using an open‐source self‐completed computerised dietary recall system Intake24 ; [48‐hour food record will be completed before the screening visit and before each testing visit.] Usual physical activity level (MET score) as assessed using the International Physical Activity Questionnaire (IAPQ) short version ; [Completed on the screening visit and each testing day and assessing physical activity from the previous week] Waist circumference, measured in centimetres using a standard tape measure at the midpoint between the iliac crest and lowest rib. [Single time point at all visits]