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Brassica Intake and Isothiocyanate Absorption

Not Applicable
Completed
Conditions
Healthy Volunteers
Interventions
Other: Controlled diet without brassica vegetables
Other: Controlled diet with brassica vegetables
Registration Number
NCT02346812
Lead Sponsor
USDA Beltsville Human Nutrition Research Center
Brief Summary

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.

Detailed Description

Not available

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
18
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 & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
ControlControlled diet without brassica vegetablesTypical American diet will be consumed, without any Brassica vegetables.
BrassicaControlled diet with brassica vegetablesBrassica vegetables will be consumed daily as part of a controlled diet.
Primary Outcome Measures
NameTimeMethod
Total isothiocyanates (ITC)24-hr

At the end of each study period, total ITC equivalents will be measured in blood and urine over a 24-hour period.

Secondary Outcome Measures
NameTimeMethod
Gastrointestinal health8-hr

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.

Fecal microbiotaEnd of 3-week study period

Fecal microbiota will be measured at the end of each 3-week study period.

Trial Locations

Locations (1)

US Department of Agriculture Beltsville Human Nutrition Research Center

🇺🇸

Beltsville, Maryland, United States

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