Effect of Quercetin Supplements on Healthy Males: a Four-Week Randomized Cross-Over Trial
|ClinicalTrials.gov Identifier: NCT01881919|
Recruitment Status : Completed
First Posted : June 20, 2013
Last Update Posted : March 24, 2015
|Condition or disease||Intervention/treatment||Phase|
|Hyperuricemia Gout Kidney Calculi Diabetes Cardiovascular Disease||Dietary Supplement: Treatment Dietary Supplement: Control||Early Phase 1|
The main goal of the research is to determine the long term effects of daily supplementation of quercetin, a compound naturally and normally present in food, on the chemical composition (uric acid ii and glucose) of blood and urine and on blood pressure, of healthy males.
Six of the volunteers will collect urine after consuming a standard meal made from fresh onion and after quercetin supplement intake, in the same way, with 3 days washout before each. The urine collected here will be analysed to check that the supplement is equivalent to the food. Stage 2 will only be conducted with supplement and placebo.
Healthy male volunteers with higher (than average) blood uric acid will be selected and will be asked to consume a standard supplement/placebo added to their own diet for 4 weeks per phase. Two arms are separated by 4 weeks resting period: quercetin supplement and placebo. Blood and urine samples will be taken every other week to detect any changes of uric acid and other biomarkers.
----- i) Quercetin is found in a variety of foods including apples, berries, brassica vegetables, capers, grapes, onions, shallots, tea, and tomatoes, as well as many seeds, nuts, flowers, barks, and leaves.
ii) Uric acid, a compound found in both in the human body and urine, is produced by the breakdown of purines, which are nitrogen-containing compounds in substances such as nucleic acids (DNA). They enter the circulation from digestion of certain foods, drinks (alcoholic beverages like beer and wine) or from normal breakdown and turnover of cells in the body. Most uric acid is removed by the kidneys and disposed of in the urine; the remainder is excreted in the stool.
|Study Type :||Interventional (Clinical Trial)|
|Actual Enrollment :||22 participants|
|Intervention Model:||Crossover Assignment|
|Masking:||Double (Participant, Investigator)|
|Primary Purpose:||Basic Science|
|Official Title:||A Double-Blind, Cross-Over, Placebo-Controlled Study Evaluating the Effect of Quercetin 500 mg Tablets on Blood Uric Acid in Healthy Males|
|Study Start Date :||February 2013|
|Actual Primary Completion Date :||April 2014|
|Actual Study Completion Date :||November 2014|
Daily intake of Quercetin supplement 500mg tablet for 28 days with meal (breakfast preferred.)
Dietary Supplement: Treatment
Address: Nature's Best, Century Place, Tunbridge Wells, Kent, TN2 3BE Phone:+44(0)1892 552030 Email:firstname.lastname@example.org
Placebo Comparator: Placebo
Daily intake of Placebo (lactose) tablet for 28 days with meal (breakfast preferred)
Dietary Supplement: Control
Address: Fagron GmbH&Co. KG, 22885 Barsbuttel, Germany Phone: +49(0)4067067680
- Risk of getting hyperuricemia assessed by the measure of plasma uric acid. [ Time Frame: Fasting blood samples are taken on day 1, day 15 and day 29 of each arm ]The change of plasma uric acid level from day 1 on day 15 and day 29 of each arm.
- Kidney excretion of uric acid: urinary uric acid level [ Time Frame: 24 h urine samples are collected on day 14 and 28 of each arm and volume is recorded ]Difference in 24-h urinary uric acid level at 14 days and 28 days between arms
- Blood pressure [ Time Frame: Blood pressure is measured on day 1 and 29 of each arm ]To monitor the compliance of subject.
- Blood glucose [ Time Frame: Fasted blood samples are collected on day 1, 15, 29 of each arm ]The change of plasma glucose level from the baseline at day 15 and day 29 of each arm.
- Metabolomic and metabonomic profiling of blood plasma [ Time Frame: Fasting blood samples are taken on day 1, day 15 and day 29 of each arm ]1H NMR (proton nuclear magnetic resonance )
- Urinary excretion of quercetin [ Time Frame: 24 h urine will be collected on day 14 and 28 of each arm and volume is recorded ]To monitor the compliance of subject.
- Subject Body Weight [ Time Frame: weight is measured on day 1 and 29 of each arm ]To monitor the compliance of subject.
- Subject Height [ Time Frame: Height is measured on day 1 and 29 of each arm ]To monitor the compliance of subject.
- Life style maintenance [ Time Frame: Recall Questionnaires about the past 28 days are required on day 1 and 29 of each arm. ]To monitor the compliance of subject.
- Primary health assessment [ Time Frame: Recall Questionnaires about history of certain disease, routine medication / supplements, allergies and exercise/diet practice at enrollment ]To set baseline for maintaining lifestyle and routine medicine for the study.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01881919
|School of Food Science and Nutrition|
|Leeds, West Yorkshire, United Kingdom, LS2 9JT|
|Study Chair:||Gary Williamson, PhD||University of Leeds|
|Principal Investigator:||Yuanlu Shi, PhD Candidate||University ofLeeds|