Plain English Summary
Background and study aims
It is now well established that consumption of specific foods and food ingredients can be associated with considerable health benefits. The potential effect of dietary modifications can be enormous in managing such major public health problems as obesity, diabetes, cardiovascular disease and cancer. Nevertheless, it is clear that appropriately designed functional foods need to be developed first. The aim of the study is to find out more about the bioavailability of health-promoting food components. Bioavailability is defined as the ease with which nutrients are freed from the food and absorbed from the digestive tract to be incorporated into the human body.
Who can participate?
Adult healthy volunteers, subject to medical examination and inclusion/exclusion criteria.
What does the study involve?
This research project will evaluate nutrikinetics and comparative bioavailability of a range of dietary supplements comprising carotenoids, resveratrol, flavanols, omega 3 fatty acids etc as well as their combinations at different doses in different food matrices, such as chocolate, butter and vegetable oils. Quantitative parameters will be assessed in the postprandial period (after meals) at different time points over the 8-week period of continuous consumption of supplemented foods. The selected functional foods will be added to the participants’ normal diet in limited amounts, practically excluding any possibility of adverse effects. Blood sample collection for evaluating nutrikinetics/bioavailability of dietary supplements will be the only minimally invasive procedure used in this study. Non-invasively collected samples of exfoliated corneocytes and sebaceous gland secretions from the surface of facial skin as well as cerumen (ear-wax) and tear fluid samples will also be used for assessing physiological effects of the dietary supplements.
What are the possible benefits and risks of participating?
There could be some benefits associated with the consumption of health-promoting dietary supplements but they are likely to be minor since the study only lasts 8 weeks. Participation will not be associated with any risks.
Where is the study run from?
When is the study starting and how long is it expected to run for?
April 2015 to March 2016
Who is funding the study?
Who is the main contact?
Dr Yvan Petyaev
Bioavailability and physiological effects of dietary antioxidants of different functional foods and beverages in volunteers
Consumption of specific foods and food ingredients can be associated with considerable health benefits. However, there are uncertainties with regard to the bioavailability of potentially beneficial food ingredients.
This study primarily addresses questions related to the bioavailability of health-promoting dietary supplements comprising carotenoids, resveratrol, flavanols, omega 3 fatty acids etc as well as their combinations at different doses in different food matrices, such as chocolate, butter and vegetable oils. We expect that this study will eventually help in developing new functional foods.
Not provided at time of registration
This study is designed to investigate the nutrikinetics and comparative bioavailability of different products containing carotenoids, flavanols, resveratrol, 3-omega fatty acids and their combinations. These products will be present at different doses in different food matrices, such as chocolate, butter and vegetable oils given to healthy volunteers in order to evaluate nutrikinetics and comparative bioavailability of the nutrients of interest. Although mild effects of dietary supplements may take place, the study can be regarded as observational.
Primary study design
Secondary study design
Patient information sheet
Not available in web format, please use the contact details to request a patient information sheet
Bioavailability and physiological effects of nutrients in healthy subjects
This observational study will include dietary supplementation. Therefore study subjects will be allocated to twelve different dietary supplementation groups (30 subjects per group).
Product formulations used in the study groups will include lycopene, lutein and resveratrol combined with either of the following food matrices: flavanol-containing 85% dark chocolate, dairy butter or flaxseed oil containing 3-omega fatty acids. Daily intake of Lycopene and Lutein will constitute 7mg (per 8g of chocolate, 30 g of dairy butter or 30ml of flaxseed oil). Daily intake of Resveratrol will constitute 120mg (per 8 g of chocolate, 30 g of dairy butter or 30ml of flaxseed oil).
The following groups (30 subjects in each) will be included:
1. Lycopene + chocolate
2. Lutein + chocolate
3. Resveratrol + chocolate
4. Lycopene + butter
5. Lutein + butter
6. Resveratrol + butter
7. Lycopene + oil
8. Lutein + oil
9. Resveratrol + oil
10. Chocolate (control)
11. Butter (control)
12. Oil (control)
Primary outcome measure
The principal objective of this research project is to assess bioavailability of a range of dietary supplements comprising carotenoids, flavanols, resveratrol, omega 3 fatty acids etc as well as their combinations in different food matrices, such as chocolate, butter and vegetable oils. Results on supplement bioavailability will constitute primary outcome measures which will be based upon analysing blood samples obtained at day 1 (postprandial) and following weeks 1, 2, 3, 4, 6, and 8 of the trial. All these results will be compared to individual pre-trial results (time point 0).
Secondary outcome measures
1. Comparative bioavailability assessment of the same group of dietary supplements comprising carotenoids, flavanols, resveratrol, omega 3 fatty acids etc as well as their combinations at different doses in different food matrices, such as chocolate, butter and vegetable oils
2. Assessment of dietary supplement effects on the characteristics of the facial skin of trial participants
3. Assessment of dietary supplement effects on the characteristics of the cerumen (ear wax) of trial participants
4. Assessment of dietary supplement effects on the lipid association with conjunctival epithelium cells in the tear fluid of trial participants
These secondary outcome measures will be determined by comparing results obtained for samples collected before trial (time point 0) with the final time point of the study (following 8 weeks of food supplement consumption).
Overall trial start date
Overall trial end date
Reason abandoned (if study stopped)
Participant inclusion criteria
1. All study participants should be healthy Caucasian males and females, age 20–80
2. Female subjects of childbearing potential should agree to undergo pregnancy tests and to use an appropriate method of contraception (i.e. oral contraceptive steroids, intrauterine device, barrier method)
3. All study participants should have findings within the normal range in medical history, physical examination, and relevant laboratory tests
4. All study participants should agree to undergo a pre-study physical examination and laboratory investigations
5. All study participants should be able to comprehend and willing to sign both statements of informed consent (for screening and phase-related procedures)
6. Only non-smokers or mild to moderate smokers (less than 10 cigarettes per day) should be enrolled in the study
Target number of participants
Participant exclusion criteria
The exclusion criteria (subjects who meet any of the following criteria are to be excluded from participating in the study):
1. The presence of a psychiatric disorder, antagonistic personality, poor motivation, emotional or intellectual problems likely to limit the validity of consent to participate in the study or limit the ability to comply with protocol requirements
2. History of or current compulsive alcohol abuse (> 10 drinks weekly), or regular exposure to other substances of abuse
3. Participation in another study with an experimental drug within 4 weeks before the initiation of the proposed dietary study
4. A major illness within 3 months before commencement of the screening period
5. History of hypersensitivity to food ingredients
6. History of bronchial asthma
7. Donation or loss of blood equal to or exceeding 500 ml during the 8 weeks before the initiation of the proposed dietary study or donation or loss blood from 250 to 500 ml in the 6 weeks before the initiation of the proposed dietary study or donation or loss of blood up to 250 ml in the 4 weeks before the initiation of the proposed dietary study
8. Resting heart rate of over 100 beats per minute or below 45 beats per minute during the screening period, either supine or standing
9. Positive testing for HIV or hepatitis B antigens
10. History of epilepsy
11. Difficulty fasting or consuming the standard meals
12. Subjects who do not tolerate venipuncture
13. Subjects on a special diet (e. g. liquid, protein, raw food diet) within 4 weeks before the initiation of the proposed dietary study
14. Drug addiction requiring treatment in the past 12 months
15. Subjects who do not agree to fully participate in wash-out period and exclude from the diet the recommended food for 4 weeks before the initiation of the study and during the study
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
Unit 3A, McClintock Building Granta Park
Funding Body Type
Funding Body Subtype
Results and Publications
Publication and dissemination plan
Publications in scientific journals and conference presentations. If trial initiation is not delayed, first papers are likely to be submitted by July 2016.
Intention to publish date
Participant level data
Available on request
Basic results (scientific)
1. 2018 results in: https://www.ncbi.nlm.nih.gov/pubmed/30319730