for males ages 20-45 (full criteria)
Healthy Volunteers
healthy people welcome
at UC Davis
study started
completion around



The investigators have previously observed a reduced level of platelet aggregation 2 hours after healthy male individuals were asked to drink extra virgin olive oil (EVOO) that provided a higher level of one specific phenolic known as oleocanthal. This study will help the investigators further determine the effects of oleocanthal-rich EVOO intake on platelet function at 2, 4 and 6 hours after intake with food compared to platelet function in the morning after an overnight fast.

Official Title

Acute Assessment of Platelet Reactivity After the Intake of Oleocanthal From Extra Virgin Olive Oil in the Fasted and Fed Condition


Fifty adult male volunteers will be asked to participate in one of two study trials that will be randomized double-blind controlled crossover trials with 2 study visits. The participants will arrive to the facility after an overnight fast, and will be asked to consume their assigned EVOO either without (trial 1) or with (trial 2) a standardized low-phenolic food (such as rice, pasta or mashed potatoes) with 40 mL of one of 2 EVOOs that are matched for their total phenolic content, but with one oil containing oleocanthal, and one with very low levels of oleocanthal. At zero, two, 4 and 6 hours after EVOO intake a blood sample will be collected for the assessment of collagen- ADP-, and AA-induced platelet aggregation, as well as an untargeted metabolomics profile.

As an assessment of phenotypic stability, a subset of individuals (n=5 per trial) that have exhibit either low or high platelet responses, will be asked to repeat the above study.


Platelet Aggregation, Nutritional and Metabolic Disease, Cardiovascular Diseases, platelet, aggregation, phenolic, olive oil, oleocanthal, Metabolic Diseases, Oleocanthal-Rich Extra Virgin Olive Oil, Oleocanthal-low Extra Virgin Olive Oil


You can join if…

Open to males ages 20-45

  • Trials 1 and 2: Male; Trial 3: Male and Female
  • 20-45 years old
  • For females, a regular 25-30-day menstrual cycle
  • Subject is willing and able to comply with the study protocols
  • Subject is willing to drink 40 mL (approximately 2 tablespoons) of olive oil
  • BMI 18.5 - 30 kg/m2
  • Weight ≥ 110 pounds

You CAN'T join if...

  • Adults who are not able to consent
  • BMI ≥ 31 kg/m2
  • Under current medical supervision
  • 1 ug/ml and 3 ug/ml collagen screening maximal platelet aggregatory response of < 65%.
  • Platelet number or mean platelet values that are outside of the normal reference range as indicated on a complete blood cell count report from the UCD Med Center
  • Current diagnosis of anemia; or a screening hemoglobin and hematocrit that is less than the normal reference range.
  • Self-reported daily use of drugs that are known to affect platelet function, such as aspirin, Excedrin, and NSAIDS
  • Females using hormonal contraception
  • Ibuprofen intolerance or allergy
  • Those with a bleeding disorder
  • Non-English speaking
  • Allergy to olives or olive oil
  • Vegetarian, Vegan, food faddists, individuals using non-traditional diets, or on a weight loss diet.
  • A history of cardiovascular disease, stroke, cancer, renal, hepatic, or thyroid disease, GI tract disorders, previous GI surgery
  • Currently taking prescription drugs or supplements
  • Indications of substance or alcohol abuse within the last 3 years
  • Not willing to stop any supplement use, including herbal, plant or botanical, fish oil, oil supplements for six weeks prior to study enrollment.
  • Not willing to refrain from olive oil consumption for 4 weeks prior to study enrollment, and throughout study enrollment
  • Self-reported malabsorption (e.g. difficulty digesting or absorbing nutrients from food, potentially leading to bloating, cramping or gas)
  • Current enrollee in a clinical research study.
  • Individuals with blood clotting or platelet defect disorders


  • Department of Nutrition accepting new patients
    Davis California 95616 United States


accepting new patients
Start Date
Completion Date
University of California, Davis
Learn more or sign up for the study here!
Study Type
Expecting 50 study participants
Last Updated