Inflammatory responses to meals with varying levels of anti-inflammatory potential: a randomised control pilot study in adults above a healthy weight

The study uses a randomised, controlled, cross over design where participants are randomised to one of three meal orders. Each participant will attend 1 screening visit and three testing visits, with a washout period between testing visits of no less than 1 week. Screening visit (x 1): Participants will have their height, weight, waist circumference and blood pressure measured. Eligible participants will be given a physical activity questionnaire (IPAQ), a 3-day food diary, and two questionnaires used to explore factors that affect their food choices, to be completed prior to their first testing visit. Pre-testing procedure: Prior to each testing session participants will be provided with a ready-prepared standardised evening meal comprised of a Healthy Choice spinach and ricotta ravioli, 50 g cheese and crackers, 250 mL 100% apple juice (3MJ, 45-65% total energy (E) carbohydrate, 25-35% E protein, and 15-25% E fat). They will be asked to consume this meal between 7 – 9 pm the night before each testing day, and will be asked to fast for 12 hours prior to their test visit. During this time they will be required to refrain from eating or drinking anything else except for water until they attend the Department of Nutrition, Dietetics & Food at the BASE Facility, Monash University, Notting Hill. They will also be asked to refrain form moderate and vigorous physical activity and alcohol consumption for 24 hours prior to each testing session. To monitor adherence to pre-intervention procedures, participants will be asked to recall at what time they consumed the standardised evening meal, how much of the standardised evening meal was consumed, and any other foods or drinks consumed during the 12 hour fasting period. They will also be asked to recall all physical activity undertaken and alcohol consumed in the 24 hour period prior to their testing visits. Testing visits (x3): Participants will be asked to come in to the lab at 8 am in the morning following an overnight fast. Their weight and waist circumference will be taken. On the morning of each test session participants will have an indwelling catheter inserted and a baseline blood draw (~15ml taken at time point t = 0). Participants will then be provided with the relevant test meal, and will be supervised to ensure all of the meal is consumed within 15 minutes. They will then remain in the laboratory for five hours, during which time 8 additional blood draws (at time points t 15, 30, 45, 60, 120, 180, 240, 300 m) will be taken, and they will not be permitted to consume any food or drink except water. During each of these testing sessions participants will also be asked to complete 3 visual analogue scales (VAS) for hunger, desire to eat, and fullness. These three VAS scales will be completed at baseline (before consuming the test meal) and then hourly for five hours (at time points t 60, 120, 180, 240 and 300 m). Lastly, participants will be asked to undertake two questionnaires about sensory evaluation and factors affecting their likelihood to prepare each of the test meals at home. Following the final blood draw the indwelling catheter will be removed. During the first testing visit participants will have their body composition (DXA scan) measured. The DXA scan will be performed prior to catheter insertion. A qualified dietitian will also take a detailed diet history. Test Meals: There are three isocaloric test meals (2.2 MJ) meals designed to have a low (-6.24, termed the anti-inflammatory meal), moderate (-2.76, termed the neutral meal) or high (+9.36, termed the pro-inflammatory meal) Dietary Inflammatory Index (DII) score. The pro-inflammatory meal, a cheese and bacon croissant, is a highly processed meal obtained from commercially available products. The neutral meal, a chicken, vegetable, red kidney bean and wholegrain pasta minestrone soup, is a typical healthy meal. The anti-inflammatory meal is an adaptation of the neutral meal, specifically designed to optimise purported anti-inflammatory compounds, including but not limited to ß-carotene, eugenol, fibre, omega-3 fatty acids, vitamin A, vitamin E and flavonoids. The anti-inflammatory meal is the intervention meal and can be described as a chicken, vegetable and red kidney bean curry, served with brown rice, flaxseeds, and a lemon kefir yogurt (2.3 MJ, with 36% energy from carbohydrate (19 g fibre), 35% energy from fat (3.4 g saturates) and 19% energy from protein).

本研究采用随机对照交叉设计，将受试者随机分配至三个餐序组别之一。每名受试者将完成1次筛选访视与3次测试访视，且两次测试访视之间的洗脱期不少于1周。
筛选访视（共1次）：受试者将接受身高、体重、腰围与血压测量。合格受试者将获得国际体力活动问卷（IPAQ）、3天饮食日记，以及两份用于探究影响其食物选择因素的问卷，需在首次测试访视前完成填写。
预测试流程：每次测试访视前，受试者将获得一份预制备的标准化晚餐，包含Healthy Choice菠菜乳清干酪馄饨、50g芝士饼干、250mL 100%苹果汁，总能量为3MJ，宏量营养素供能占比为：碳水化合物45%~65%、蛋白质25%~35%、脂肪15%~25%。受试者需在每次测试日前一晚的19:00~21:00间食用该晚餐，并需在测试访视前12小时禁食，期间仅可饮用白开水，直至抵达莫纳什大学诺丁山校区BASE设施的营养与饮食学系。此外，受试者需在每次测试访视前24小时内避免进行中高强度体力活动与饮酒。为监测受试者对干预前流程的依从性，需受试者回忆标准化晚餐的食用时间、食用量，以及禁食12小时期间摄入的其他任何食物或饮品；同时需回忆测试访视前24小时内进行的所有体力活动与摄入的酒精。
测试访视（共3次）：受试者需在隔夜空腹后于次日早上8:00抵达实验室，随后测量体重与腰围。每次测试访视当日早上，将为受试者置入留置导管并采集基线血液样本（t=0时刻，约15mL）。随后为受试者提供对应测试餐，并全程监督确保其在15分钟内食用完全部餐食。受试者需在实验室停留5小时，期间将在t=15、30、45、60、120、180、240、300分钟时刻共采集8次额外血液样本，且期间仅可饮用白开水。每次测试访视期间，受试者还需完成三份针对饥饿感、进食欲望与饱腹感的视觉模拟量表（Visual Analogue Scale, VAS）：该量表将在基线时刻（食用测试餐前）完成，随后每小时完成一次，共持续5小时（对应t=60、120、180、240、300分钟时刻）。最后，受试者需完成两份关于感官评价，以及影响其在家制备各测试餐可能性的因素的问卷。末次采血完成后，将移除留置导管。
在首次测试访视中，受试者将接受身体成分检测（双能X线吸收法（Dual-energy X-ray absorptiometry, DXA）扫描），该检测需在置入留置导管前完成。此外，一名合格营养师将为受试者采集详细饮食史。
测试餐：本研究共设置三份等热量测试餐（每份2.2MJ），其饮食炎症指数（Dietary Inflammatory Index, DII）评分分别为低（-6.24，命名为抗炎餐）、中等（-2.76，命名为中性餐）与高（+9.36，命名为促炎餐）。促炎餐为芝士培根可颂，属于市售高度加工食品。中性餐为鸡肉、蔬菜、红腰豆与全麦意式蔬菜浓汤，是一款典型的健康餐食。抗炎餐为中性餐的改良版本，专门设计用于优化据称具有抗炎作用的成分，包括但不限于β-胡萝卜素、丁子香酚、膳食纤维、Omega-3脂肪酸、维生素A、维生素E与类黄酮。抗炎餐为本研究的干预餐，具体为鸡肉蔬菜红腰豆咖喱，搭配糙米、亚麻籽与柠檬开菲尔酸奶，总能量为2.3MJ，其中碳水化合物供能占比36%（含19g膳食纤维）、脂肪供能占比35%（含3.4g饱和脂肪）、蛋白质供能占比19%。