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Provitamin A Absorption and Conversion With Avocados

This study is ongoing, but not recruiting participants.
Sponsor:
Collaborator:
Hass Avocado Board
Information provided by (Responsible Party):
Steven Schwartz, Ohio State University
ClinicalTrials.gov Identifier:
NCT01432210
First received: September 4, 2011
Last updated: October 9, 2011
Last verified: October 2011
History of Changes
  Purpose

Vitamin A is necessary in the human diet. The form of vitamin A found in fruits and vegetables is not "active" and must be converted to the active form in the human body. However, information on the ability of humans to absorb and convert vitamin A to the active form is still lacking. In this study, the investigators will observe the absorption and conversion of vitamin A from orange tomato sauce and/or carrots after a meal with fat (from avocado fruit) and a meal without fat. The investigators will also test whether eating these foods might protect the blood against damage that could lead to heart disease.


Condition Intervention
Healthy
 Other: Post-prandial Feeding Study

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Bio-availability Study
Intervention Model: Crossover Assignment
Masking: Open Label
Primary Purpose: Basic Science
Official Title: Enhancing Human Intestinal Absorption of Carotenoids and Bioconversion of Carotene to Vitamin A in the Presence of Hass Avocados

Resource links provided by NLM:

MedlinePlus related topics: Vitamin A
U.S. FDA Resources

Further study details as provided by Ohio State University:

Primary Outcome Measures:
  • Post-prandial levels of provitamin A and vitamin A [ Time Frame: Nine post-prandial blood samples will be taken over twelve hours ] [ Designated as safety issue: No ]
    The absorption of and conversion of provitamin A carotenoids into vitamin A will be measured after the consumption of a carotenoid-rich meal. The meal will be served both with and without avocado as a source of lipid.


Secondary Outcome Measures:
  • post-prandial antioxidant status of blood [ Time Frame: comparing baseline vs. 5 hour status ] [ Designated as safety issue: No ]
    The ability of a carotenoid-rich meal to reduce the susceptibility of blood lipoproteins to oxidative stress will be tested. A modified trolox equivalent antioxidant capacity (TEAC) assay will be used.


Estimated Enrollment: 24
Study Start Date: September 2011
Estimated Study Completion Date: March 2012
Estimated Primary Completion Date: January 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Tomato Meal
A tomato meal will be fed with and without avocado.
 Other: Post-prandial Feeding Study
Carrot Meal
A carrot meal will be fed with and without avocado.
 Other: Post-prandial Feeding Study

Detailed Description:

The primary objective of this study will be to demonstrate that adding avocados to a carotene rich meal will promote the absorption of provitamin A carotenoids and enhance the delivery of greater quantities of vitamin A. This objective will be accomplished by quantitation of the immediate post-prandial plasma concentrations of parent carotenoids and vitamin A metabolites after subjects consume a meal with or without avocado in combination with a serving of tomato sauce (containing nutritionally relevant amounts of beta-carotene) or carrots.

The secondary objective of this study will be to determine if higher levels of carotenoids and other antioxidants transported in the bloodstream will have a protective role in promoting cardiovascular health. This objective will be accomplished by testing the oxidation capacity of lipoprotein fractions before and after meal supplementation.

  Eligibility

Ages Eligible for Study:   18 Years to 70 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Total cholesterol (140 to 200 mg/dL)
  • BMI 17 to 30
  • Age 18-70 years

Exclusion Criteria:

  • Lactating, pregnant, or plan to be pregnant during study
  • Tobacco use (cigarettes or chewing tobacco)
  • Metabolic disease
  • Malabsorption disorders
  • History of cancer, esophageal, gastric, or intestinal ulcers
  • History of liver or kidney insufficiency or failure
  • Allergies to tomatoes or tomato products
  • Allergies to carrots
  • Allergies to avocados
  • Obesity (BMI>30)
  • Hypercholesterolemia (total cholesterol> 200mg/dL)
  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT01432210

Locations
United States, Ohio
The Ohio State University Clinical Research Center
Columbus, Ohio, United States, 43210
Sponsors and Collaborators
Ohio State University
Hass Avocado Board
Investigators
Principal Investigator: Steven J Schwartz, Ph.D. Ohio State University
  More Information

No publications provided

Responsible Party: Steven Schwartz, Professor, Ohio State University
ClinicalTrials.gov Identifier: NCT01432210     History of Changes
Other Study ID Numbers: 2011H0159, 60030575
Study First Received: September 4, 2011
Last Updated: October 9, 2011
Health Authority: United States: Institutional Review Board

Keywords provided by Ohio State University:
post-prandial absorption
provitamin A carotenoids
vitamin A
 avocado
tomato
carrot

Additional relevant MeSH terms:
Carotenoids
Vitamin A
Beta Carotene
Antioxidants
Molecular Mechanisms of Pharmacological Action
Pharmacologic Actions
 Protective Agents
Physiological Effects of Drugs
Vitamins
Micronutrients
Growth Substances

ClinicalTrials.gov processed this record on May 21, 2013