Effects of Omega-3 Fatty Acids on Markers of Inflammation

Effects of Plant and Marine Omega-3 (w-3) Fatty Acids on Inflammatory Markers In Insulin Resistant Adults

The major purpose of this study is to examine the effect of two sources of dietary omega-3 fatty acids, each given at two doses, on potential health benefits related to cardiovascular disease prevention. The two sources of dietary omega-3 fatty acids will be fish oil, and flaxseed oil.

Study Overview

• Status: Completed
• Conditions: Hypertension; Obesity; Insulin Resistance; Hypertriglyceridemia
• Intervention / Treatment: Dietary supplement: Fish Oil; Dietary supplement: Flaxseed Oil; Dietary supplement: Placebo

Detailed Description

The primary aim of this study is to examine the effect of two sources of dietary omega-3 fatty acids, each given at two doses, on potential health benefits related to cardiovascular disease prevention. The two sources of dietary omega-3 fatty acids will be fish oil, and flaxseed oil. Each will be given at a lower dose that could realistically be achieved from food sources alone, and at a higher dose that could not realistically be achieved from food alone and would require supplementation. The outcomes being studied are markers of inflammation. The subjects being studied are those with elevated risk factors for diabetes and heart disease that meet the criteria for the "metabolic syndrome". These are the people who are currently not diabetic, and who have not been diagnosed yet with heart disease, who are at risk of developing these diseases and who would likely benefit the most from the omega-3 therapy should it prove to be effective.

• Study Type: Interventional
• Enrollment (Actual): 102
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • California
    • Stanford, California, United States, 94305
      • Stanford University School of Medicine

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:Gender:

• Both women and men
• Age: > or = 18 years
• Ethnicity and race: All ethnic and racial backgrounds welcome
• As defined in ATP III of the National Cholesterol Education program, the metabolic syndrome will be diagnosed as presence of at least three of the following, which will be measured at the screening clinic visit:

Central obesity as measured by waist circumference:

• Men: Greater than 40 inches

• Women: Greater than 35 inches

  • Fasting blood triglycerides greater than or equal to 150 mg/dL
  • Blood HDL cholesterol:
• Men: Less than 40 mg/dL

• Women: Less than 50 mg/dL

  • Blood pressure greater than or equal to 130/85 mmHg

    • Fasting glucose greater than or equal to 100 mg/dL

Planning to be available for clinic visits and bottle pick-ups for the 8 weeks of study participation

Ability and willingness to give written informed consent

No known active psychiatric illness.

Exclusion Criteria:Daily intake of dietary supplements containing omega-3 FAs within the past month.

• Fasting blood glucose > 140 mg/dL
• Significant liver enzyme abnormality
• AST or ALT more than 2 times the upper limit of normal and/or
• Bilirubin more than 50% the upper limit of normal
• Renal disease as measured at baseline:
• Serum creatinine > 1.30 mg/dL, or
• Calculated creatinine clearance < 71 mL/min

• Self reported personal history of:

  • Clotting disorders
  • Clinically significant atherosclerosis (e.g., CAD, PAD)
  • Malignant neoplasm
  • Ongoing infection
  • Inflammatory disease (e.g., rheumatoid arthritis)

• Subjects currently receiving the following medications (self report):

  • Anti-Inflammatory drugs
  • Lipid lowering drugs including statins
  • Anti-hypertensive drugs
  • Anti-coagulant drugs
• Body Mass Index (BMI) greater than or equal to 40.
• Pregnant or Lactating
• Inability to communicate effectively with study personnel

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

5

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Low-dose Flaxseed Oil; 2.2 g ALA (alpha-linolenic acid) per day	Dietary supplement: Flaxseed Oil; Flaxseed oil capsule
Experimental: High-dose Flaxseed Oil; 6.6 g ALA (alpha-linolenic acid) per day	Dietary supplement: Flaxseed Oil; Flaxseed oil capsule
Experimental: Low-dose Fish Oil; 1.2 g EPA+DHA (700 mg EPA and 500 mg DHA) per day	Dietary supplement: Fish Oil; Fish oil capsule
Experimental: High-dose Fish Oil; 3.6 g EPA+DHA (2.1 g EPA and 1.5 g DHA) per day	Dietary supplement: Fish Oil; Fish oil capsule
Placebo Comparator: Placebo; 4 g or 6 g soybean oil per day	Dietary supplement: Placebo; Soybean oil capsule

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change from baseline in inflammatory markers (MCP-1, IL-6, and sICAM-1) at 8 weeks.	Change was calculated as the value at 8 weeks minus the value at baseline	Baseline and 8 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change from baseline in red blood cells (RBC) Fatty Acids at 8 weeks.	Change was calculated as the value at 8 weeks minus the value at baseline	Baseline and 8 weeks
Change from baseline in low-density lipoprotein (LDL) cholesterol at 8 weeks.	Change was calculated as the value at 8 weeks minus the value at baseline	Baseline and 8 weeks
Change from baseline in high-density lipoprotein (HDL) cholesterol at 8 weeks.	Change was calculated as the value at 8 weeks minus the value at baseline	Baseline and 8 weeks
Change from baseline in triglycerides at 8 weeks.	Change was calculated as the value at 8 weeks minus the value at baseline	Baseline and 8 weeks

Collaborators and Investigators

• Sponsor: Stanford University
• Collaborators: National Center for Complementary and Integrative Health (NCCIH)

Publications and helpful links

General Publications

• Dewell A, Marvasti FF, Harris WS, Tsao P, Gardner CD. Low- and high-dose plant and marine (n-3) fatty acids do not affect plasma inflammatory markers in adults with metabolic syndrome. J Nutr. 2011 Dec;141(12):2166-71. doi: 10.3945/jn.111.142240. Epub 2011 Oct 26.

Helpful Links

• Study description and summary of results

Study record dates

Study Major Dates

• Study Start: April 1, 2007
• Primary Completion (Actual): December 1, 2008
• Study Completion (Actual): December 1, 2008

Study Registration Dates

• First Submitted: May 20, 2010
• First Submitted That Met QC Criteria: May 21, 2010
• First Posted (Estimate): May 24, 2010

Study Record Updates

• Last Update Posted (Estimate): February 22, 2023
• Last Update Submitted That Met QC Criteria: February 18, 2023
• Last Verified: February 1, 2023

More Information

Terms related to this study

• Keywords: Metabolic syndrome; Adults; Omega-3 fatty acids; Fish oil
• Additional Relevant MeSH Terms: Glucose Metabolism Disorders; Metabolic Diseases; Hyperinsulinism; Lipid Metabolism Disorders; Hyperlipidemias; Dyslipidemias; Insulin Resistance; Hypertriglyceridemia
• Other Study ID Numbers: SU-05042010-5842; R21AT003465-01 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No