Bioavailability of Carotenoids Added Into Processed Foods
Condition: Cardiovascular Disease
MeSH terms: Cardiovascular Diseases
Study type: Interventional

Summary: 
      Carotenoids are a family of pigments found abundantly in fruits and vegetables. They are
      responsible for the colour of many fruits and vegetables such as tomatoes, melon, peppers and
      orange coloured fruits and vegetables. Carotenoids such as beta-carotene are important for
      the human body as precursors of vitamin A. They are also thought to be important as
      anti-oxidants and may help protect against cancer and heart disease. Although many foods are
      rich sources of carotenoids poor bioavailability often limits the amounts that are absorbed
      and available for metabolism in humans.

      Devising practical ways and means of increasing carotenoid bioavailability could lead to
      better health outcomes. Processed foods are now widely eaten by many, both for their taste
      and convenience. No studies have thus far looked at the bioavailability of carotenoids that
      have been added into processed foods. Thus the purpose of this study is to investigate the
      bioavailability of carotenoids that have been incorporated into processed food products
      (bread and mayonnaise).
    

Detailed description: 
      Carotenoids are a diverse group of natural-occurring fat-soluble pigments. Whilst over 600
      different types have been characterised around 20 have been found in human tissue in the
      postprandial state, however, over 90% of these absorbed carotenoids are made up of 6 specific
      types (alpha-Carotene, beta-carotene, Lycopene, Lutein, Zeaxanthin and Cryptoxanthin)

      There is good evidence to suggest that carotenoids play a notable role in human health both
      through their pro-vitamin activity and as biological antioxidants. Carotenoids are believed
      to be responsible for the beneficial effects of fruits and vegetables in preventing human
      chronic diseases such as cancer and cardiovascular disease. Increasing fruit and vegetables
      intakes in individuals can sometimes be difficult and unsustainable, therefore, increasing
      bioavailability may be an effective alternative approach to maximise health outcomes.

      A notable number of vegetables are rich sources of carotenoids, however, the amounts
      available to the human body for metabolism are often small due to poor bioavailability. For
      instance, studies have shown that bioavailability of carotenoids from carrots and tomatoes
      can be as low as 1-3%. The bioavailability of carotenoids has been shown to depend on factors
      such as their source, degree of cooking, processing, mechanical breakdown, presence of fat
      and interactions between carotenoids. Whilst the presence of fat significantly increases
      carotenoid absorption, the oil type, quantity and form it is in all affect bioavailability.

      Recent work suggests that carotenoid bioavailability improves when fat is present in the form
      of mayonnaise rather than as plain oil. This may be due to the emulsion properties of
      mayonnaise which allows better solubilisation of amphiphilic compounds such as carotenoids.
      Mayonnaise has also been shown to be more miscible in gastric juices (compared to plain oil)
      and this too may be contributing to the greater absorption of carotenoids.

      The present study builds upon this previous work and studies carotenoid bioavailability in
      processed food systems. Using a bread-mayonnaise meal the study compares carotenoid
      bioavailability when it is incorporated either into the bread or the mayonnaise. Furthermore,
      the study investigates the impact of mayonnaise on the bioavailability of carotenoids
      incorporated into a processed food (bread). The study will focus on the bioavailability of
      three principle carotenoids found in foods, alpha-carotene, beta-carotene and lycopene.
      Carrot and tomato are used as the sources of carotenoids.

      HYPOTHESIS Carotenoid bioavailability is influenced by the food matrix in which they are
      contained.

      OBJECTIVES

        1. To compare the acute-phase bioavailability (systemic and gut absorption) of targeted
           carotenoids (alpha-carotene, beta-carotene and lycopene) when they are incorporated into
           the different processed food matrices (bread and mayonnaise)

        2. Study how mayonnaise affects the acute bioavailability of carotenoids incorporated into
           a processed food.
    

Intervention name(s): Control; Vegetable bread only; Plain bread with vegetable mayonnaise; Vegetable bread with plain mayonnaise
Intervention type(s): Dietary Supplement; Dietary Supplement; Dietary Supplement; Dietary Supplement
Intervention description(s): The bread and mayonnaise in this meal does not have vegetable powders incorporated into them. Hence this meal does not contain carotenoids.; A vegetable powder (carrot and tomato) containing bread portion will be served alone. The amount of vegetable powder in the bread portion will be standardised to contain a known amount of carotenoids.; Plain bread will be served with a vegetable powder (carrot and tomato) containing mayonnaise. The amount of vegetable powder in the mayonnaise will be standardised to contain a known amount of carotenoids.; A vegetable powder (Carrot and tomato) containing bread portion will be served with plain mayonnaise. The amount of vegetable powder in the bread portion will be standardised to contain a known amount of carotenoids
Other intervention name(s): plain bread with plain mayonnaise
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: None (Open Label)
Primary purpose: Health Services Research
Keywords: Processed foods; Carotenoids in plasma, urine and faeces; alpha-carotene; beta-carotene; Vitamin A; Lycopene; Gut absorption; Bread; Mayonnaise; Bioavailability; Fruits and Vegetables; Inflammation; Oxidative Stress