Healthy
Conditions
Keywords
flavanols, procyanidins, absorption, cocoa polyphenols, Flavanol and procyanidin absorption in healthy volunteers
Brief summary
The purpose of this study is to determine whether or not the intake of dietary procyanidins (oligomers of flavanols) contribute to the systemic presence of flavanols in healthy humans.
Detailed description
Flavanols and their oligomeric derivatives, the procyanidins, are plant-derived compounds normally present in the human diet. Accumulating data demonstrate a causal role for flavanols in mediating the cardiovascular benefits associated with the consumption of flavanol-/procyanidin-containing foods. Evidence for a direct, causal role for procyanidins in this context is far less profound. As this is often based on the poor absorption of procyanidins, it has been proposed that procyanidins may indirectly contribute to the systemic presence of bioactive compounds via derivatives generated from the breakdown or catabolism of procyanidins in the gastrointestinal tract. These postulated 'breakdown products' include: i) flavanols, putatively generated by acid hydrolysis in the stomach, and ii) series of phenolic compounds, including 5-(3,4-dihydroxyphenyl)-gamma-valerolactone, that are produced from procyanidin catabolism by the gut microbiome. Verification or rejection of these suppositions could significantly impact the interpretation of epidemiological-/dietary intervention data, and the design of food-content data bases. To address this question, healthy volunteers will consume specially designed cocoa-based dairy drinks containing flavanols and procyanidins (dimers to decamers) either together or individually.
Interventions
OTHERFlavanol- and procyanidins-containing drink
Single oral intake of a cocoa-based dairy drink containing flavanols \[monomer\] and procyanidins \[dimers to decamers\]
OTHERProcyanidins-containing drink
Single oral intake of a ocoa-based dairy drink containing procyanidins \[dimers to decamers\]
OTHERFlavanol-containing drink
Single oral intake of a cocoa-based dairy drink containing flavanols \[monomers\]
Sponsors
University of California, Davis
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
ALL
Age
18 Years to 70 Years
Healthy volunteers
Yes
Inclusion criteria
* A normal blood chemistry and liver function * Fasting blood cholesterol and triglycerides \< 300 mg/dl and \< 3.0 mmol/l, respectively * BMI \< 30 kg/m2 will be considered. * Volunteers must be able to read and speak English fluently, and thus, fully understand the researchers, research protocols, and their rights as a research volunteer.
Exclusion criteria
* A history of cardiovascular disease, stroke, uncontrolled hypertension (\> 160/90 mm), renal, hepatic, or thyroid disease, GI tract disorders, previous GI surgery, metabolic syndrome, diabetes, taking cholesterol-lowering medication, hormone replacement therapy, antioxidant supplements, on aspirin therapy or taking anticoagulants, or on a medically prescribed diet. * A history of psychiatric illness or an allergy to peanuts.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Area under the curve described by the concentration of flavanol metabolites in plasma versus time | After consumption at time points 0, 1, 2 and 4 h | The concentration of flavanol metabolites in plasma is expressed in nmol/L. Flavanol metabolites encompass a series of O-sulfonated, O-glucuronidated and O-methylated flavanol derivatives generated in the gastrointestinal tract and liver after flavanol absorption. |
| Peak plasma concentration of flavanol metabolites | After consumption at time points 0, 1, 2 and 4 h | The concentration of flavanol metabolites in plasma is expressed in nmol/L. Flavanol metabolites encompass a series of O-sulfonated, O-glucuronidated and O-methylated flavanol derivatives generated in the gastrointestinal tract and liver after flavanol absorption. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Amount of flavanol metabolites excreted in urine | urine collected up to 24h post-consumption | The amount of flavanol metabolites excreted in urine is expressed in µmol. Flavanol metabolites encompass a series of O-sulfonated, O-glucuronidated and O-methylated flavanol derivatives generated in the gastrointestinal tract and liver after flavanol absorption. |
| Amount of 5-(3,4-dihydroxyphenyl)-gamma-valerolactone metabolites in urine | urine collected up to 24 h post-consumption | The amount of 5-(3,4-dihydroxyphenyl)-gamma-valerolactone metabolites excreted in urine is expressed in µmol. 5-(3,4-dihydroxyphenyl)-gamma-valerolactone metabolites encompass a series of O-sulfonated and O-glucuronidated derivatives generated in the gastrointestinal tract and liver after 5-(3,4-dihydroxyphenyl)-gamma-valerolactone absorption. |
Countries
United States
Outcome results
None listed