Acute Meat and Alternative Intake (PRotEin DIet SatisfacTION Trial 3)
Condition: Diet, Healthy; Protein; Disease
Study type: Interventional

Summary: 
      Introduction: Protein rich foods that are alternatives to farm-grown meat have received
      considerable consumer attention. Whilst meat alternatives were once niche food products aimed
      at vegetarians, they are increasingly marketed to omnivores and "flexitarians", thus
      contributing to a trend for reductions in red meat intakes [1]. Studies to date have
      addressed the environmental benefit, plus consumer perceptions and acceptability of meat
      alternatives [2, 3, 4], yet there is surprisingly a paucity of data compared the nutritional
      and digestive differences to meat. The aim of this trial is to compare the digestive
      consequences of pasture-fed and grain-finished, beef versus a plant-based meat analogue
      blinded meal.

      Methods and analyses: Healthy, young (20-34 y) participants will be asked to consume three
      separate meals in a crossover, blinded investigation followed by five hours of blood testing
      and questionnaires to assess the digestive consequences of meat and a plant-based meat
      analogue. The three meals will include either pasture-fed, or grain-finished, or laboratory
      based protein alternative as a mixed meal, in random order, separated by one week minimum.
      Plasma samples will be assessed amino acid content, neurotransmitter proteins, chylomicron
      fatty acid distribution and general health indices.

      Ethics and dissemination: The trial has been granted ethical approval by the Ministry of
      Health, Health and Disability Ethics Committee (Ref: 19/STH/226). All results originating
      from this study will be submitted for publication in scientific journals and presented at
      meetings.
    

Detailed description: 
      Introduction: Red meat consumption contributes important nutrients to the diet, including
      essential amino acids, long chain and complex lipids, vitamins (including B12) and minerals
      (including iron and zinc) [5]. While supplying these important nutrients, red meat may
      contain components which may negate optimal health such as the saturated fat content and
      nitrates, that are added during processing [5]. The degree to which red meat affects health
      is likely related to its inherent nutritional profile, the quantity consumed and any
      processing (e.g. nitrates or cooking techniques). Regardless, the simple notion of a complex
      whole-food containing single nutrients which are 'good' or 'bad' for health is now considered
      overly simplistic [6]. For example, to reduce heart disease, nutritional guidelines now
      suggest an increase in polyunsaturated fats at the expense of saturated fat, rather than a
      complete reduction of all fats [6].

      Alongside the controversy over the health consequences of red meat, recent attention has
      focused on the possibility of using "plant-based" proteins as an alternative to red meat
      consumption. The search for meat alternatives has resulted in a sharp increase in the
      production of novel "plant-based" meat analogues that have been designed to replicate the
      taste and eating experience of red-meat. To date there are very few studies addressing the
      nutritional differences between traditional red meat and plant-based meat analogues, and the
      nutritional differences that arise due to different production systems. Given the nutritional
      composition of red meat is likely to be influenced by the farming and feeding practices of
      the animals, production procedures and end-user cooking techniques [7], these differences
      need to be accounted for in the research design and application.

      Aims: To investigate the digestive responses to an acute intake of pasture-fed beef,
      grain-finished beef, lamb and a plant based meat-analogue consumed as a component of a mixed
      meal. This study is part of a larger programme to understand the nutritional implications of
      consuming New Zealand, pasture-fed red meat as part of a balanced diet.

      Study Design and Setting: The study is designed as randomised cross-over trial to capture
      biological difference in postprandial nutrient dynamics. Research subjects will act as their
      own controls and will consume each meal (pasture raised, grain-fed beef, lamb and a meat
      alternative meal) on a separate occasion in random order. The study compares exemplars of
      pasture-fed New Zealand beef, grain-finished New Zealand beef, lamb and a meat analogue. The
      plant-based meat analogue has been selected on the basis of its macronutrient profile
      (protein and fat) and appearance in order to that best matches that of meat.

      The digestion and metabolism of key nutrients in beef will be measured immediately after the
      ingestion of a single meal. This experimental setting will also be used to examine some
      subjective qualities of the meal experience, such as satisfaction score (i.e., liking,
      satisfaction, enjoyment, satiety, appetite) and gastrointestinal score (i.e., comfort,
      fullness, bloating, rumbling, flatulence, faecal urgency, diarrhoea).
    

Intervention name(s): Food. Beef, Pasture-raised; Food. Beef, Grain-fed; Food. Meat alternative; Food, Lamb
Intervention type(s): Other; Other; Other; Other
Intervention description(s): Pasture-raised beef; Grain-fed beef; Meat alternative; Lamb
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Basic Science
Keywords: protein; amino acid; diet; health; meat products; bioavailability