Biomarkers in Post-Menopausal Women Receiving Flaxseed

A Pilot Study of the Flaxseed Effects on Hormones and Lignans: Role of Race, Genes, and Gut Microbiome

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT01698294

Enrollment

258

Registered

2012-10-02

Start date

2012-12-14

Completion date

2017-06-08

Last updated

2022-05-09

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

No Evidence of Disease

Keywords

gut microbiome, hormones, women, race, phytoestrogens

Brief summary

This randomized clinical trial studies biomarkers in post-menopausal women receiving flaxseed. Studying samples of blood, urine, and feces in the laboratory from participants receiving flaxseed may help doctors understand the effects of flaxseed on biomarkers.

Detailed description

PRIMARY OBJECTIVES: I. To determine associations between the composition of the gut bacterial communities and baseline levels of the mammalian lignans and steroid hormones. II. To determine how variation in gut microbial community composition and in steroid hormone and xenobiotic metabolizing genes affects the metabolism of mammalian lignans and steroid hormones after exposure to a lignan-rich food (flaxseed). III. To determine how these associations differ by race (i.e., African American and European American women). OUTLINE: Participants are randomized to 1 of 2 treatment groups. GROUP I: Participants receive flaxseed orally (PO) daily for 6 weeks. After a usual diet washout period of 8 weeks, patients crossover to Group II. GROUP II: Participants maintain a usual diet for 6 weeks. After a usual diet washout period of 8 weeks, patients crossover to Group I. After completion of study treatment, participants are followed up for 30 days.

Interventions

OTHERClinical Observation

Participants maintain usual diet and undergo clinical observation

DIETARY_SUPPLEMENTFlaxseed

Given PO

OTHERLaboratory Biomarker Analysis

Correlative studies

OTHERQuestionnaire Administration

Ancillary studies

Study design

Allocation

RANDOMIZED

Intervention model

CROSSOVER

Primary purpose

BASIC_SCIENCE

Masking

NONE

Eligibility

Sex/Gender

FEMALE

Age

45 Years to 80 Years

Healthy volunteers

Yes

Inclusion criteria

* Participant must understand the investigational nature of this study and sign an Independent Ethics Committee/Institutional Review Board approved written informed consent form prior to receiving any study related procedure * Participant must be a non-Hispanic white or non-Hispanic black (self-reported race) woman 45 to 80 years of age and postmenopausal; postmenopausal will be defined as no menstrual cycle in the past 12 months; women with a hysterectomy but with intact ovaries will be included if aged \>= 55 years * Willingness to comply with the requirements of the study

Exclusion criteria

* Unwilling or unable to follow protocol requirements * Self-reported race other than non-Hispanic white or non-Hispanic black * Use, in the 2 months prior to week 1 visit, of antibiotics, hormone replacement therapy, nonprescription hormones or herbal supplements for menopausal symptoms, or flaxseed supplements * Nut or seed allergy * Self-reported inflammatory bowel disease * Gastric bypass * Use of thyroid replacement medication (Synthroid or similar) for \< 1 year * Any condition which in the investigator's opinion deems the participant an unsuitable candidate to receive flaxseed * Chemotherapy/radiation within the past year * Body weight greater than 400 pounds (limit of Tanita scale)

Design outcomes

Primary

Measure	Time frame
Relative percent of Eubacteria composition from quantitative polymerase chain reaction (qPCR) associated with lignan levels	Up to week 21
Steroid hormone and lignans levels after exposure to a lignan-rich food (flaxseed)	Up to week 21

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 13, 2026