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Soy, Selenium and Breast Cancer Risk

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ClinicalTrials.gov Identifier: NCT00555386
Recruitment Status : Completed
First Posted : November 8, 2007
Last Update Posted : September 25, 2008
Information provided by:

Study Description
Brief Summary:
There is evidence to suggest that some dietary components can reduce the risk of breast cancer. In this pilot study two such components, isoflavones (compounds found in soy products) and selenium, will be given to women classed as at moderate to high risk of the disease. The aim is to determine some novel biomarkers of risk and to see the effect of supplementation on them.

Condition or disease Intervention/treatment
Breast Cancer Risk Dietary Supplement: Soy and Selenium

Detailed Description:

The high incidence of breast cancer, its relatively long development phase and the financial burden to the NHS in relation to treatment makes it a prime target for dietary preventative strategies. Epidemiological and experimental investigations suggest several key dietary components that may reduce breast cancer, in particular isoflavones and selenium. Few dietary intervention studies have been conducted to investigate putative protective effects, but with our growing understanding of cancer biology and the application of new -omics technologies it is now possible to use early biomarkers of risk to assess the potential efficacy of intervention studies.

In this pilot project, we will employ a combination of disciplines to examine the effect of dietary intervention in a group of women defined by NICE guidelines as being at increased risk (moderate-high) of developing breast cancer, using metabolomics to assess the tractability of biomarkers in response to the dietary intervention. Such trials are urgently needed to examine the protective effects of diet in women classified at increased risk and who are still in the 'zone of reversibility'. The results of this study will be used to justify and optimise larger scale intervention trials and ultimately to develop appropriate dietary recommendations for the prevention of breast cancer.

A dietary intervention study based on a randomised double-blind parallel design will be conducted in 30 pre-menopausal women (age 35-50) at moderate to high risk of developing breast cancer. The metabolomic profiles of urine and serum samples (collected at baseline and after dietary intervention) will be assessed. Participants will be randomised into two groups; the placebo group (consuming 6g of non-supplemented chocolate per day) and the supplemented group (consuming 6g of chocolate containing both soy and selenium per day). The intervention will last for the duration of one menstrual cycle.

Study Design

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 27 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double (Participant, Investigator)
Primary Purpose: Prevention
Official Title: A Pilot Study to Determine the Effect of Dietary Intervention on Novel Biomarkers of Breast Cancer Risk.
Study Start Date : April 2007
Primary Completion Date : May 2008
Study Completion Date : August 2008

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Breast Cancer
U.S. FDA Resources

Arms and Interventions

Arm Intervention/treatment
Active Comparator: 1
6g of chocolate (supplemented with selenium and isoflavones) per day for the duration of one menstrual cycle (25-35 days)
Dietary Supplement: Soy and Selenium
6g of chocolate per day Control group with no supplementation Active group 50mg of soy protein isolate + 200µg selenium in the form of MSC
Placebo Comparator: 2
6g of chocolate (control) per day for the duration of one menstrual cycle (25-35 days)
Dietary Supplement: Soy and Selenium
6g of chocolate per day Control group with no supplementation Active group 50mg of soy protein isolate + 200µg selenium in the form of MSC

Outcome Measures

Primary Outcome Measures :
  1. To determine the effect of supplementation with selenium and isoflavones on biomarkers of breast cancer risk. [ Time Frame: 25-35 days ]

Secondary Outcome Measures :
  1. Identify novel biomarkers of breast cancer risk through metabolomic analysis of samples collect. [ Time Frame: 25-35 days ]

Eligibility Criteria

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Ages Eligible for Study:   35 Years to 50 Years   (Adult)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Pre menopausal women (age 35-50)at moderate to high risk of breast cancer based on family history (NICE guidelines)
  • Attending Breast Clinic at NNUH
  • Willing to consume 6g of chocolate per day for 25-35 days
  • Regular menstrual cycle of 25-35 days in length

Exclusion Criteria:

  • Current or previous diagnosis of breast cancer or cancer of any other site
  • Diagnosis of hypertension (requiring active treatment)/diabetes/ coronary heart disease/ gastrointestinal disease/ any other systemic disease requiring treatment
  • Regularly taking any prescribed medication within the last six months (including oral contraceptives)
  • Fitted with a hormone releasing device
  • Pregnant or lactating in the previous 12 months
  • Using laxatives or antacids more than once a week
  • Routinely taking soy or selenium supplements in the last twelve months
  • Regularly taking any dietary or herbal supplements in the last six months
  • Participation in any intervention study (soy or selenium) in the previous twelve months
  • Parallel participation in another research study involving either dietary or medical intervention or sampling of biological fluids/materials
  • Blood donation within sixteen weeks of study start/finish
  • BMI <18.5 or >35
  • Allergy to any chocolate/dairy/soy-based food products
Contacts and Locations

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00555386

United Kingdom
Institute of Food Research
Norwich, Norfolk, United Kingdom, NR4 7UA
Norfolk and Norwich University Hospital
Norwich, Norfolk, United Kingdom, NR4 7UY
University of East Anglia
Norwich, Norfolk, United Kingdom, NR47TJ
Sponsors and Collaborators
University of East Anglia
Quadram Institute
Big C Local Cancer Research and Care
Clinical Research and Trials Unit (Norfolk & Norwich University Hospital, UK)
Principal Investigator: Aedin Cassidy, PhD University of East Anglia
More Information


Responsible Party: Professor Aedin Cassidy, University of East Anglia
ClinicalTrials.gov Identifier: NCT00555386     History of Changes
Other Study ID Numbers: R14697
First Posted: November 8, 2007    Key Record Dates
Last Update Posted: September 25, 2008
Last Verified: September 2008

Keywords provided by University of East Anglia:
Breast Cancer Risk

Additional relevant MeSH terms:
Breast Neoplasms
Neoplasms by Site
Breast Diseases
Skin Diseases
Molecular Mechanisms of Pharmacological Action
Protective Agents
Physiological Effects of Drugs
Trace Elements
Growth Substances