Effects of Enriched Fruit Juice on Blood Glucose Levels After a Meal in Healthy Subjects
试验速览
- 阶段
- 不适用
- 入组人数
- 24
- 试验地点
- 2
- 主要终点
- Changes in maximal incremental plasma glucose level (iCmax) between baseline and endpoint within the intervention group vs. placebo control.
研究概览
简要总结
Results from a large number of studies in humans have shown that diets rich in foods that give lower glucose response bring lower risk of type 2 diabetes. Polyphenols, naturally found in fruits, vegetables and grains, have shown the potential to attenuate post-prandial blood glucose spikes following a carbohydrate-rich meal, through partial inhibition of the main enzymes of carbohydrate digestion and reduction in glucose and fructose transport from the gut after digestion and by enhancing the insulin action after glucose reaches the bloodstream.
This study is designed to determine whether polyphenols, as normally and naturally present in food extracts and beverages, added to a carbohydrate-rich meal, can lower blood glucose levels after its consumption, and hence lower its glycaemic index, and if this effect is mediated through effects on insulin and other hormones. The study is designed as an acute, double-blind, randomised, placebo-controlled crossover trial in 24 healthy subjects with normal glycaemic response to white bread. Participants will be asked to consume either white bread with pomegranate juice enriched with extracts from grape seeds and apple peels or white bread with placebo drink. The effects on plasma glucose levels, levels of hormones and other biomarkers involved in postprandial response will be determined over 3 hours after the consumption.
详细描述
Consumption of carbohydrate-rich foods or sugary drinks affects blood glucose levels. Results from a large number of studies in humans have shown that diets rich in foods that give lower glucose response beneficially affect elevated fasting blood glucose and insulin levels, increase the sensitivity to insulin, contribute to the reduction of body weight and lipids levels and ultimately bring lower risk of type 2 diabetes.
Blood glucose responses depend on the amount and type of carbohydrate(s) present in the meal. Difference in post-prandial blood glucose response to different types of carbohydrates is mainly due to the different rate of their digestion. However, response to the same carbohydrate-rich food can be different between different individuals. Blood glucose levels after carbohydrate-rich meal are shown to be significantly higher in subjects on high-fat diet, in overweight or obese people, or in subjects with different levels of digestive enzymes.
Results from in vitro studies indicate the potential of polyphenols, naturally found in fruits, vegetables and grains, to attenuate post-prandial blood glucose spikes following a carbohydrate-rich meal. It was previously shown that different polyphenols can slow down carbohydrate digestion through partial inhibition of the main enzymes involved, can decrease glucose and fructose transport from the gut after digestion and can improve the action of insulin after glucose reaches the bloodstream.
In the previous study it was shown that pomegranate juice attenuates the increase in blood glucose levels after a starchy meal. This effect is, at least partly, the result of hindered starch digestion by polyphenols present in pomegranate juice.
The present study will determine whether polyphenols, as normally and naturally present in food extracts and beverages, added to a carbohydrate-rich meal, can lower blood glucose levels after its consumption, and hence lower its glycaemic index, and if this effect is mediated through effects on insulin and other hormones or determined by the individual levels of digestive enzymes.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Prevention
- 盲法
- Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- 18 Years 至 65 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Fasting glucose ≤ 5.6 mM;
- •Body mass index (BMI) ≤ 30;
- •Max glucose after the consumption of app. 109g of white bread less than about 8-9 mM (which is typical for the subjects we have measured previously);
排除标准
- •Participating in another trial that requires blood collection;
- •Diagnosed with any chronic illness (including diabetes, hypertension etc.);
- •On long term prescribed medication (except contraceptives);
- •Pregnant or lactating;
- •On a special diet or dietary regimen (for weight management or if regularly consuming fruit extract supplements);
- •Allergy to fruits vegetables or pollen.
结局指标
主要结局
Changes in maximal incremental plasma glucose level (iCmax) between baseline and endpoint within the intervention group vs. placebo control.
时间窗: Baseline, 15 min, 30 min, 45 min, 60 min, 90 min, 120 min, 150 min, 180 min.
The incremental glucose levels will be determined for each time point (at 15, 30, 45, 60, 90, 120, 150 and 180 min) as the change in plasma glucose levels after the consumption of enriched pomegranate juice or placebo drink concomitantly with white bread, compared to the glucose levels before the consumption of test meals (baseline value, t=0min).
次要结局
- Changes in plasma insulin levels between baseline and endpoint within the intervention group vs. placebo control.(Baseline, 15 min, 30 min, 45 min, 60 min, 90 min, 120 min, 150 min, 180 min.)
- Changes in area under the curve of incremental plasma glucose levels (iAUC) in the intervention group vs. placebo control.(Baseline, 15 min, 30 min, 45 min, 60 min, 90 min, 120 min, 150 min, 180 min.)
- Changes in plasma gastric inhibitory peptide (GIP) levels between baseline and endpoint within the intervention group vs. placebo control.(Baseline, 15 min, 30 min, 45 min, 60 min, 90 min, 120 min, 150 min, 180 min.)
- Changes in glucagon-like peptide-1 (GIP-1) levels between baseline and endpoint within the intervention group vs. placebo control.(Baseline, 15 min, 30 min, 45 min, 60 min, 90 min, 120 min, 150 min, 180 min.)
研究者
Gary Williamson
Professor Gary Williamson
University of Leeds