Effects of Vitamin D and Marine Omega-3 Fatty Acids on Anemia

November 18, 2025 updated by: Nancy Berliner, Brigham and Women's Hospital

Effects of Vitamin D and Marine Omega-3 Fatty Acids on Anemia in the Elderly

The VITamin D and OmegaA-3 TriaL (VITAL; NCT01169259) is a randomized clinical trial in 20,000 U.S. men and women studying whether taking daily dietary supplements of vitamin D3 (2000 IU) or omega-3 fatty acids (Omacor® fish oil, 1 gram) reduces the risk of developing cancer, heart disease, and stroke in people who do not have a prior history of these illnesses. This ancillary study is being conducted among VITAL participants and will study whether vitamin D or fish oil: (A) in the overall VITAL cohort, reduces the number of persons diagnosed with anemia and (B) in a subcohort of 900 participants seen in Boston, effects long-term changes of the proteins in blood in both anemic and non-anemic individuals who provide blood samples at the start of the study and again 2 years later.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Active, not recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

The VITamin D and OmegA-3 Trial (VITAL; NCT01169259) is a randomized clinical trial of vitamin D (in the form of D3 [cholecalciferol]) and marine omega-3 fatty acid (eicosapentaenoic acid [EPA] + docosahexaenoic acid [DHA]) supplements in the primary prevention of cancer and cardiovascular disease.

Eligible participants will be assigned by chance (like a coin toss) to one of four groups: (1) daily vitamin D3 and omega-3; (2) daily vitamin D3 and omega-3 placebo; (3) daily vitamin D and omega-3; or (4) daily vitamin D placebo and omega-3 placebo. Participants have an equal chance of being assigned to any of these four groups and a 3 out of 4 chance of getting at least one active agent.

Participants in all group will take two pills each day--one softgel that contains either vitamin D3 or vitamin D placebo and one capsule that contains either omega-3 or omega-3 placebo. Participants will receive their study pills in convenient calendar packages via U.S. mail.

Participants will also fill out a short (15-20 minute) questionnaire each year. The questionnaire asks about health; lifestyle habits such as physical exercise, diet, and smoking; use of medications and dietary supplements; family history of illness, and new medical diagnoses. Occasionally participants may receive a phone call from study staff to collect information or to clarify responses on the questions.

If a participant reports a new medical diagnosis of anemia on the short questionnaires, he or she will be invited to participate in this sub-study. If the participant consents, his or her medical record will be reviewed to confirm the diagnosis of anemia. We expect roughly 1,100 individuals to develop anemia while on the study.

Of the expected 20,000 participants in the VITAL trial, approximately 1,000 participants will be seen in Boston and given the opportunity to participate in optional research blood draws. This sub-study expects to receive approximately 10mL of the samples collected from 900 of these participants. This portion of blood will be used to evaluate the amount of different proteins in both anemic and non-anemic individuals. Blood samples will be collected at baseline and two years later.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
2000

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • 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 Locations

  • United States
    • Massachusetts
      • Boston, Massachusetts, United States, 02115
        • Brigham and Women's Hospital

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

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

46 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Description

Participants in VITAL (NCT 01169259) who do not have anemia at baseline and who report a diagnosis of anemia on the VITAL follow-up questionnaires are eligible to participate in this ancillary study.

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: Prevention
  • Allocation: Randomized
  • Interventional Model: Factorial Assignment
  • Masking: Triple

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Active Comparator: Vitamin D + fish oil
Dietary Supplement: Vitamin D3 (cholecalciferol), 2000 IU per day. Other Name: cholecalciferol Drug: omega-3 fatty acids (fish oil) Omacor, 1 capsule per day. Each capsule of Omacor contains 840 milligrams of marine omega-3 fatty acids (465 mg of eicosapentaenoic acid [EPA] and 375 mg of docosahexaenoic acid [DHA]).
Drug: omega-3 fatty acids (fish oil)
Dietary supplement: Vitamin D3 .
Active Comparator: Vitamin D + fish oil placebo
Dietary Supplement: Vitamin D3 (cholecalciferol), 2000 IU per day. Other Name: cholecalciferol Dietary Supplement: Fish oil placebo Fish oil placebo
Dietary supplement: Vitamin D3 placebo
Dietary supplement: Vitamin D3 .
Active Comparator: Vitamin D placebo + fish oil

Drug: omega-3 fatty acids (fish oil) Omacor, 1 capsule per day. Each capsule of Omacor contains 840 milligrams of marine omega-3 fatty acids (465 mg of eicosapentaenoic acid [EPA] and 375 mg of docosahexaenoic acid [DHA]).

Dietary Supplement: Vitamin D3 placebo Vitamin D placebo
Dietary supplement: Fish oil placebo
Drug: omega-3 fatty acids (fish oil)
Active Comparator: Vitamin D placebo + fish oil placebo
Dietary Supplement:Vitamin D3 placebo Vitamin D placebo Dietary Supplement: Fish oil placebo Fish oil placebo
Dietary supplement: Fish oil placebo
Dietary supplement: Vitamin D3 placebo

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Incidence of Anemia
Time Frame: 2 years
We will compare the number of participants who took vitamin D supplements who developed anemia and the number of participants who did not take vitamin D who developed anemia to current rates of development of anemia in the U.S. We will further examine whether the effect of vitamin D supplementation on anemia risk varies by race/ethnicity, gender, or baseline levels of 25(OH)D.
2 years
Long-term Changes in Blood Protein Levels
Time Frame: 2 years
We will examine the samples from the 900 boston participants and determine whether vitamin D supplementation affects long-term changes in hemoglobin, red blood cell (RBC) indices, hepcidin, and erythropoietin (EPO) levels. These protein levels will be assessed in both anemic and non-anemic individuals in fresh samples at baseline [pre-randomization] and at 2 years of follow-up post-randomization.
2 years

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Incidence of Anemia
Time Frame: 2 years
We will compare the number of participants taking fish oil supplements who developed anemia and the number of participants not taking fish oil supplements who developed anemia to the current rates of development of anemia in the U.S. We will also study the number participants diagnosed with anemia over 4 years of follow-up and whether the effect of taking fish oil supplements on anemia risk varies by race/ethnicity, gender, or baseline levels of omega-3 fatty acid.
2 years
Long-term Changes in Protein Levels
Time Frame: 2 years
We will examine the samples collected from the 900 Boston participants and determine whether fish oil supplementation affects long-term changes in hemoglobin, red blood cell(RBC) indices, hepcidin, and erythropoietin (EPO) levels. These protein levels will be assessed in both anemic and non-anemic individuals in fresh samples at baseline [pre-randomization] and at 2 years of follow-up post-randomization.
2 years

Collaborators and Investigators

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

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Brigham and Women's Hospital

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
National Heart, Lung, and Blood Institute (NHLBI)
National Center for Complementary and Integrative Health (NCCIH)
Office of Dietary Supplements (ODS)

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Nancy Berliner, MD, Brigham and Women's Hospital

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Helpful Links

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 (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
November 1, 2012

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
December 28, 2025

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
December 28, 2025

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
June 29, 2012

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
June 29, 2012

First Posted (Estimated)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
July 3, 2012

Study Record Updates

Last Update Posted (Estimated)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
November 21, 2025

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 18, 2025

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
November 1, 2025

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 2012P001526

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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