Investigating the Bioavailability of Broccoli Extract Supplements

May 1, 2026 updated by: Emily Ho, Oregon State University

The goal of this clinical trial is to compare how much glucoraphanin and sulforaphane from 3 different versions of broccoli extract supplements is absorbed into the body and excreted in urine. This study involves generally healthy adults age 18-60 years. The supplements contain glucoraphanin and myrosinase enzyme, both naturally occurring in cruciferous vegetables. Once ingested, glucoraphanin is converted to the bioactive compound sulforaphane, which is thought to have numerous health benefits, including cancer prevention.

Participants will:

  • consume 3 different versions of broccoli extract supplements (glucoraphanin will range from 35-70 mg)
  • complete 3 separate 24 hour study cycles
  • submit blood and urine samples for 24 hours
  • follow diet restrictions (no cruciferous vegetables or condiments or phytochemical/herbal supplements for 1 week prior to and during each study cycle)

Study Overview

Detailed Description

This study aims to compare the bioavailability of 3 different versions of a broccoli extract supplement in generally healthy adults age 18-60 years who do not smoke or are not pregnant/lactating. The supplements contain glucoraphanin and myrosinase enzyme, both naturally occurring in cruciferous vegetables. Once ingested, glucoraphanin is converted to the bioactive compound sulforaphane, which is thought to have numerous health benefits, including cancer prevention. The amount of glucoraphanin that subjects will take will range from 35-70 mg. Glucoraphanin, sulforaphane, and sulforaphane metabolites will be measured in plasma and urine for 24 hours (plasma: 0, 0.5, 1, 2, 4, 8, and 24 hours after supplement consumption; urine: 0-2, 2-4, 4-8, and 8-24 hour after supplement consumption).

Study Type

Interventional

Enrollment (Estimated)

12

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • Healthy adults, 18-60 years of age
  • Willing to stop taking herbal and phytochemical (plant-based extract or phytochemical) supplements for 1 week prior to and during each study cycle
  • Willing to stop cruciferous vegetable intake 1 week prior to and during each study cycle
  • Must be able to give written informed consent

Exclusion Criteria:

  • Body Mass Index (BMI) <18.5 or >30.0 kg/m2
  • Tobacco use, including e-cigarettes, or smoking of any substance (e.g. cannabis) in the past three months
  • Pregnancy, breastfeeding, or planning to become pregnant before completing the study
  • Engaging in vigorous exercise more than 7 hours per week
  • Have a significant acute or chronic illness such as cardiovascular disease, kidney or liver disease, diabetes, thyroid disorder, or radiation or chemotherapy treatment for cancer within the past five years
  • Use of medications to control cholesterol (e.g. statins, cholestyramine) or fat absorption (e.g. orlistat)
  • Have had bariatric surgery (e.g. gastric bypass, gastric banding, sleeve gastrectomy, etc.), other gastrointestinal procedure (e.g. cholecystectomy) or disorders (e.g. Crohn's disease, celiac disease, ulcerative colitis)
  • Allergic to broccoli, moringa, mustard, or maitake mushrooms
  • Weighs less than 110 pounds
  • Diagnosis of sickle cell disease

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: Randomized
  • Interventional Model: Crossover Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: 35 mg glucoraphanin
Participants will swallow by mouth 1 tablet of Avmacol Extra Strength with coating.
Participants will swallow by mouth 1 tablet Avamacol Extra Strength with coating (35 mg glucoraphanin per tablet)
Active Comparator: 60 mg glucoraphanin
Participants will chew and swallow by mouth 2 tablets of Avmacol chewable wafers (30 mg glucoraphanin each)
Participants will chew and swallow by mouth 2 wafers Avmacol chewable wafers (30 mg glucoraphanin per wafer)
Active Comparator: 70 mg glucoraphanin
Participants will swallow by mouth 2 tablets of Avmacol Extra Strength with coating (35 mg glucoraphanin each)
Participants will swallow by mouth 2 tablets Avamacol Extra Strength with coating (35 mg glucoraphanin per tablet)

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Urine sulforaphane
Time Frame: 0, 2, 4, 8, and 24 hours
Change from baseline levels of sulforaphane in urine
0, 2, 4, 8, and 24 hours
Urine sulforaphane metabolites
Time Frame: 0, 2, 4, 8, and 24 hours
Change from baseline levels of sulforaphane in urine
0, 2, 4, 8, and 24 hours
Plasma glucoraphanin
Time Frame: 0, 1, 2, 4, 8, and 24 hours
Change from baseline levels of plasma glucoraphanin
0, 1, 2, 4, 8, and 24 hours
Plasma sulforaphane
Time Frame: 0, 1, 2, 4, 8, and 24 hours
Change from baseline levels of plasma sulforaphane
0, 1, 2, 4, 8, and 24 hours
Plasma sulforaphane metabolites
Time Frame: 0, 1, 2, 4, 8, and 24 hours
Change from baseline levels of plasma sulforaphane metabolites
0, 1, 2, 4, 8, and 24 hours

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Emily Ho, PhD, Oregon State University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

September 1, 2026

Primary Completion (Estimated)

September 1, 2027

Study Completion (Estimated)

September 1, 2028

Study Registration Dates

First Submitted

April 27, 2026

First Submitted That Met QC Criteria

April 27, 2026

First Posted (Actual)

May 4, 2026

Study Record Updates

Last Update Posted (Actual)

May 7, 2026

Last Update Submitted That Met QC Criteria

May 1, 2026

Last Verified

April 1, 2026

More Information

Terms related to this study

Other Study ID Numbers

  • LPI-2026-2211

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

We will not share IPD.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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