Brassica Intake and Isothiocyanate Absorption

Brassica Intake and Isothiocyanate Absorption: Intake Patterns May Have Implications for Cancer Prevention by Dietary Brassica Vegetables

Healthy individuals (n=18) will participate in 2 controlled-feeding study periods that are 3 weeks each in length: 1) Control diet 2) Brassica diet. The control diet will consist of typical American foods and will be free of Brassica vegetables and free of glucosinolates and isothiocyanates. The Brassica diet will contain the control diet plus glucosinolate/isothiocyanate treatment foods. There will be a break of 3 weeks in between study periods. Blood, urine, and fecal samples will be collected at the end of each study period. Eligible participants will be selected based on genotype for glutathione S-transferase (GST), which has been shown to influence the potential protective role of dietary Brassicas. Half the participants (n=9) will be GSTM1-positive individuals and half (n=9) will have the GSTM1-null genotype.

Study Overview

• Status: Completed
• Conditions: Healthy Volunteers
• Intervention / Treatment: Other: Controlled diet with brassica vegetables; Other: Controlled diet without brassica vegetables

• Study Type: Interventional
• Enrollment (Actual): 18
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Maryland
    • Beltsville, Maryland, United States, 20705
      • US Department of Agriculture Beltsville Human Nutrition Research Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 21 years to 70 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Between 21 - 70 years of age
• Not currently taking glucosinolate/ITC containing supplements
• Voluntarily agree to participate and sign an informed consent document
• Free of cancer (never diagnosed or cancer-free for at least 5 y)

Exclusion Criteria:

• Pregnant, lactating, or intend to become pregnant during the study period
• Known allergy or intolerance to Brassica vegetables
• History of bariatric surgery or nutrient malabsorption disease (such as celiac disease) or other metabolic disorders requiring special diet recommendations
• Use of tobacco products
• Use of certain medications (prescription or over-the-counter) that may interfere with the study objectives
• Type 2 diabetes requiring the use of diabetes pills, insulin, or non-insulin shots
• Use of blood-thinning medications such as Coumadin (warfarin), Dicumarol, or Miradon (anisindione)
• Unable or unwilling to give informed consent or communicate with study staff
• Self-report of alcohol or substance abuse within the past 12 months and/or current acute treatment or rehabilitation program for these problems (long-term participation in Alcoholics Anonymous is not an exclusion)
• Other medical, psychiatric, or behavioral factors that in the judgment of the Principal Investigator may interfere with study participation or the ability to follow the intervention protocol

Study Plan

How is the study designed?

Design Details

• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Brassica; Brassica vegetables will be consumed daily as part of a controlled diet.	Other: Controlled diet with brassica vegetables; Participants will be fed a controlled diet containing foods of a typical American diet.
Other: Control; Typical American diet will be consumed, without any Brassica vegetables.	Other: Controlled diet without brassica vegetables; Participants will be fed a controlled diet containing foods of a typical American diet.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total isothiocyanates (ITC)	At the end of each study period, total ITC equivalents will be measured in blood and urine over a 24-hour period.	24-hr

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Fecal microbiota	Fecal microbiota will be measured at the end of each 3-week study period.	End of 3-week study period
Gastrointestinal health	At the end of each 3-week study period, urine will be collected for 8 hours as part of the lactulose-mannitol test, which is a measure of gastrointestinal health.	8-hr

Collaborators and Investigators

• Sponsor: USDA Beltsville Human Nutrition Research Center

Publications and helpful links

General Publications

• Charron CS, Vinyard BT, Ross SA, Seifried HE, Jeffery EH, Novotny JA. Absorption and metabolism of isothiocyanates formed from broccoli glucosinolates: effects of BMI and daily consumption in a randomised clinical trial. Br J Nutr. 2018 Dec;120(12):1370-1379. doi: 10.1017/S0007114518002921.

Study record dates

Study Major Dates

• Study Start: January 1, 2015
• Primary Completion (Actual): April 1, 2015
• Study Completion (Actual): April 1, 2015

Study Registration Dates

• First Submitted: January 15, 2015
• First Submitted That Met QC Criteria: January 20, 2015
• First Posted (Estimate): January 27, 2015

Study Record Updates

• Last Update Posted (Estimate): April 30, 2015
• Last Update Submitted That Met QC Criteria: April 29, 2015
• Last Verified: January 1, 2015

More Information

Terms related to this study

• Other Study ID Numbers: HS49