Millets and Oats MRI
Condition: Healthy
Study type: Interventional

Summary: 
      Breakfast porridges made from milled grains are commonly eaten worldwide. Traditionally
      different grains are used in different countries. For example, oats are more common in the
      Anglo-Saxon countries whilst millet is very common in parts of India and Africa. However the
      nutritional value of different grains and their potential effects on the body may vary
      dramatically: for example the effect on blood sugar, on how fast the stomach empties after
      eating and how full people may feel.

      RESEARCH QUESTION: The investigators think that a pearl millet breakfast will cause a smaller
      rise in blood sugar compared with an oat breakfast containing the same number of calories.
      The investigators also think that there will be a difference in how full people feel and how
      fast their stomach will empty. These 2 breakfasts will be fed to each one of 26 healthy
      volunteers, one week apart. A safe medical imaging method (MRI) will be used to look at how
      quickly the breakfast empty from the stomach and how this affects the small bowel. Blood
      glucose levels will be measured using a finger prick test (the same as used by diabetics) and
      some small blood samples will be taken from a vein in the arm to measure the chemicals
      released by the gut after feeding gut hormones.
    

Detailed description: 
      Background: Porridge breakfasts from various grains are a staple source of energy for many
      populations worldwide. The grains used in the porridges differ between regions, mostly due to
      the crops historically grown. For example, oats are more common in the Anglo-Saxon countries
      whilst millet is very common in parts of India and Africa. Consumption of whole grains has
      been associated with a variety of health benefits ranging from lower blood glucose levels,
      improved insulin responses, reduced cholesterol and increased diversity of the microbiota. Of
      particular interest to this study are recent suggestions that different grains, and
      particularly millet grains, may have enhanced health benefits on glucose and insulin
      metabolism. This may be due to different rates of digestion and absorption, for example,
      because of grain specific differences in starch digestibility. This could affect gastric
      emptying and, in turn, post prandial glycaemia and impact on satiety. However little is known
      about possible differences in gastric emptying between breakfast porridges from different
      grains and possible relationship with glucose, insulin and appetite.

      The research group in Nottingham has world-leading expertise in imaging foods in the body and
      gastrointestinal function using non-invasive Magnetic Resonance Imaging (MRI) techniques
      which are particularly well suited for this kind of investigations study.

      Aims:

        1. to collect data on postprandial glucose levels and hormone peptide response of
           isoenergetic breakfast porridges made from oats and pearl millet.

        2. to collect data on their gastric emptying and satiety.

        3. to compare postprandial glucose levels, gastric emptying and satiety for the treatments
           4. to explore relationships between glucose levels, gastric emptying and satiety.

      Experimental protocol and methods: 26 healthy volunteers will participate in this 2-way
      study. They will attend one morning for each study, with the studies separated by
      approximately a week. Before the test meal, and after that approximately every 15 min for 2
      hours the level of sugar (glucose) in their blood will be measured using the finger prick
      method, as diabetics commonly do to monitor their blood sugars. Venous blood samples will
      also be collected from a cannula placed in the forearm to measure gut hormones such as
      Peptide YY, GIP, GLP-1 and insulin. The subjects will be scanned on a research dedicated 1.5T
      MRI scanner. The subjects will be scanned at baseline, immediately after the test meal and
      then every 30 minutes for 2 hours postprandially. At baseline and every time the subjects
      come out of the MRI scanner they will be asaked to rate their feelings of fullness, hunger
      and appetite on 100mm VAS scales. Each subject will be fed two isoenergetic breakfast meals
      -one on each visit: Oat and Pearl millet breakfast porridge sourced from supermarkets or food
      manufacturers. These will be cooked in water to avoid confounding factor with milk. The test
      breakfast will have 220 kcal (slightly higher than a commonly recommended average portion of
      ~185 kcal). After this the subjects will be asked to eat as much of a pasta meal as they wish
      and note how much they have eaten as an objective measure of food consumption. The subjects
      will also complete a food diary for the rest of the day.

      Measurable endpoints/ statistical power Primary endpoint: Incremental Area Under the Curve of
      post prandial blood glucose up to 2h (AUC2h) Secondary endpoints: Area Under the Curve of
      post prandial gastric volumes up to 2h (AUC2h), postprandial hormone peptide response,
      insulin and post prandial VAS scores up to 2h.

      Descriptive and exploratory measurements: Time to Peak of blood glucose; Area Under the Curve
      for appetite (Fullness, Hunger, Prospective food consumption) up to 2h. The amount of pasta
      meal eaten ad libitum. Energy intake for the day from food diaries.

      Correlations between blood, MRI and satiety data. Using Satiety data (Hunger) from our pilot
      study, we can calculate sample size needed using a crossover, paired design with alpha=0.05
      and a power of 80% using n=26 participants.

      The data will be assessed for normality using the Shapiro-Wilk test and other such methods as
      appropriate. Where normally distributed, endpoints will be assessed using parametric methods.

      T test (primary endpoint) and AUC2h (secondary endpoints). T test of Time to Peak.
      Correlation (Pearson's or Spearman) between blood glucose, MRI and satiety data.
    

Intervention name(s): Oats breakfast porridge; Pearl (bajra) breakfast porridge
Intervention type(s): Other; Other
Intervention description(s): Isoenergetic and isovolumteric oats breakfast porridge; Isoenergetic and isovolumteric pearl (bajra) breakfast porridge
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Single (Investigator)
Primary purpose: Basic Science
Keywords: MRI; blood glucose; porridge; breakfast; satiety; plasma peptides