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Trial record 2 of 8 for:    oleuropein

Effect of Olives on Glycaemic Response in Vivo

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT02669693
Recruitment Status : Completed
First Posted : February 1, 2016
Last Update Posted : March 23, 2017
Information provided by (Responsible Party):
Gary Williamson, University of Leeds

Brief Summary:

This research is aimed at determining whether the presence of oleuropein in olives (Olea europaea L.) has any lowering effect on post-prandial blood glucose levels. Volunteers will be required to consume commercially available olives together with white bread, and their glycaemic response will be measured. The blood glucose response of bread will be determined initially as a control/reference. Food samples and control will be consumed in random order.

The recent rise in the cases of Diabetes mellitus in both children and adults has raised a concern for the need to proffer immediate solutions amongst scientists in the fields of medicine food science and nutrition. One of the approaches of reducing postprandial hyperglycaemia and high glucose spikes is to impede digestion and absorption of starch. This is potentially achieved through the inhibition of the activities of starch digesting enzymes namely alpha amylase and alpha glycosidase. There are currently some antidiabetic drugs such as acarbose and miglitol which have been quite efficient in these inhibitory functions but not without associated side effects and complications such as liver toxicity, etc, arising from to long term usage of such drugs. It therefore becomes imperative for natural substitutes from food sources to be explored as better alternatives. At the moment several plant foods are under investigation as suitable alternatives, and olives appear to be quite promising in this regard. There are quite a few studies that have reported the inhibitory activities of olives oleuropein on alpha amylase in vitro but information on in vivo testing is very scarce.

It is expected that the research outcome will be a gateway to the reduction and control of the incidence of diabetes mellitus.

Condition or disease Intervention/treatment Phase
Diabetes Dietary Supplement: bread without olives Dietary Supplement: bread with olives Not Applicable

Detailed Description:

Prior to commencement of the study, potential volunteers will be given a clear, concise Participant Information Sheet and Informed Consent Form by the investigator to read, complete and sign in their own time. The investigator will answer all questions to the satisfaction of the individual and will not influence the decision of taking part in the study. The participants will be free to withdraw from the study at any point without providing a reason. The written consent form will be signed and dated at least 2 days prior to enrolment in the study by the volunteers and the Investigator. It will be photocopied and one copy will be kept by the Investigator (for the study records) and one by the volunteer. Participation by the volunteers is conditional upon receiving the written consent by the volunteer.

Candidates will be asked to complete a questionnaire in order to assess their suitability for the study. The information pertains to their lifestyle and may be considered a sensitive issue, however each volunteer will be assured of confidentiality and that participation is entirely voluntary. The information on the questionnaire will include height, weight, gender, age and relevant medical history. Confidentiality of all participants' information will be maintained. Identification will be coded using random ID numbers that will be assigned on the day of study. All data collected will be treated as confidential and stored securely in a locked filing cabinet according to current University regulations. The linkage between individual identity and ID number will be kept in written form only and stored in a locked filling cabinet in a restricted access area, thus it will not be possible to identify individual participants from the ID numbers. Data evaluation will only be performed using ID numbers. In accordance with the University guidelines on the password protected M-drive of the University server, anonymised data will be stored for at least 5 years.

Blood glucose will be measured after consumption of test meal/control using a commercially available glucometer which is available to be bought by any member of the public and people already use them on their own. It measures glucose concentrations immediately and meets the accuracy requirement for the ISO 15197 standard. A drop of blood is enough and is obtained from participants by means of a mild finger prick using a sterile puncture device designed for this purpose for each time point. The finger prick protocol is the WHO/FAO 1998 glycaemic index approved protocol. Nine (9) finger pricks will be needed (0, 15, 30, 45, 60, 90, 120, 150 and 180minutes) will be needed per study session.

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 16 participants
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)
Primary Purpose: Basic Science
Official Title: Effect of Olives on Glycaemic Response in Vivo
Study Start Date : December 2015
Actual Primary Completion Date : June 2016
Actual Study Completion Date : July 2016

Arm Intervention/treatment
Placebo Comparator: bread without olives
Intervention (no olives): Subjects will consume a meal of 109 g white bread and 200 of ml water, and post-prandial blood glucose measured over a 3 hour period.
Dietary Supplement: bread without olives
Active Comparator: bread with olives
Intervention (olives 100 g): Subjects will consume a meal of 109 g white bread, 100 g of olives and 200 of ml water, and post-prandial blood glucose measured over a 3 hour period.
Dietary Supplement: bread with olives

Primary Outcome Measures :
  1. Post-prandial blood glucose concentration [ Time Frame: 180 minutes ]

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   18 Years to 75 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Aged 18-75
  • Fasting glucose (blood glucose level before breakfast) 3.9 -5.9mmol/L

Exclusion Criteria:(self assessed)

  • Diabetic
  • on long term prescribed medication (except contraceptives)
  • pregnant or lactating
  • on special diet (for losing weight or fruit extracts supplements)

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT02669693

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United Kingdom
School of Food Science and Nutrition, University of Leeds
Leeds, West Yorkshire, United Kingdom, LS2 9JT
Sponsors and Collaborators
University of Leeds
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Principal Investigator: Gary Williamson, PhD University of Leeds

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Responsible Party: Gary Williamson, Professor, University of Leeds Identifier: NCT02669693    
Other Study ID Numbers: MEEC 12-037a
First Posted: February 1, 2016    Key Record Dates
Last Update Posted: March 23, 2017
Last Verified: March 2017
Keywords provided by Gary Williamson, University of Leeds:
Olives, oleuropein