The Effects of Natural Versus Man-Made Trans Fatty Acids on Lipoprotein Profiles: A Pilot Study

This study has been completed.
Sponsor:
Collaborator:
National Cattlemen's Beef Association
Information provided by:
Children's Hospital & Research Center Oakland
ClinicalTrials.gov Identifier:
NCT00535886
First received: September 21, 2007
Last updated: May 5, 2008
Last verified: September 2007
  Purpose

The purpose of this study is to test the effects of natural vs. man-made trans fatty acids (trans fats) on blood cholesterol.


Condition Intervention
Cardiovascular Disease
Diabetes
Dyslipidemia
Dietary Supplement: Man-made Trans FA
Dietary Supplement: Natural Trans FA
Dietary Supplement: Oleic Acid

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single Blind (Subject)
Primary Purpose: Prevention
Official Title: The Effects of Natural Versus Man-Made Trans Fatty Acids on Lipoprotein Profiles: A Pilot Study

Resource links provided by NLM:


Further study details as provided by Children's Hospital & Research Center Oakland:

Primary Outcome Measures:
  • The primary outcome measure will be the ratio of total to high density lipoprotein (HDL) cholesterol. Blood draws will take place at screening, three weeks, and five weeks. [ Time Frame: Five weeks ]

Secondary Outcome Measures:
  • Related secondary outcome measures include concentrations of low density lipoprotein (LDL) cholesterol, HDL cholesterol, triglyceride (TG) and Lp(a) measured at screening, three weeks, and five weeks. [ Time Frame: Five weeks ]

Enrollment: 15
Study Start Date: November 2005
Study Completion Date: April 2006
Arms Assigned Interventions
Active Comparator: Elaidic Acid Dietary Supplement: Man-made Trans FA
EA as 6% of total energy
Experimental: Vaccenic Acid Dietary Supplement: Natural Trans FA
VA as 6% of total energy
Placebo Comparator: Oleic Acid Dietary Supplement: Oleic Acid
OA as 6% of total energy

Detailed Description:

Since the purpose of the study is to determine the statistical power required for a definitive study testing and comparing the effects of two trans fatty acids, vaccenic and elaidic acid, on lipoprotein profiles, no hypotheses will be specified.

Specific Aims:

  1. To determine the variability in the lipid and lipoprotein response to diets enriched in natural versus man-made trans fats in order to appropriately power a larger scale clinical study
  2. To optimize the delivery of trans fat-enriched diets through the development of supplemental food items

The adverse health effects of trans fatty acids (TFA) on cardiovascular disease (CVD) risk have been established in a number of metabolic and epidemiological studies [Willett 1993, Hu 1997, Ascherio 1996, Pietinen 1997, Oomen 2001]. Trans fats are fatty acids with 18 carbon chains and one or more double bond(s). The hydrogen atoms of the double bond(s) are in a configuration (trans rather than cis) that results in the straightening of a normally kinked unsaturated fatty acid chain. Trans fats occur naturally in low quantities in dairy and beef products, but have also been artificially introduced to the food supply by the process of the hydrogenation of vegetable oils [Mann 1994]. Only two studies linking the consumption of trans fatty acids with an increased risk of CVD have distinguished between the effects of man-made versus naturally occurring trans fatty acids [Willett 1993, Oomen 2001].

It has been suggested that the relationship between trans fatty acids and coronary heart disease is specifically attributable to man-made trans fatty acids. In fact, some of the trans fats that occur naturally in animal products, in particular, conjugated linoleic acid (CLA), may have beneficial health effects. CLA has been shown to be anti-carcinogenic [Ip 2003], anti-atherogenic [McLeod 2004] and anti-diabetic [Rainer 2004]; it has also been shown to enhance the immune response and have positive effects on growth and energy partitioning. As a precursor to CLA, vaccenic acid (VA), another trans fatty acid found in dairy and beef products, may also provide health benefits. Bioconversion of VA to CLA has been recently demonstrated [Turpeinen 2002]. The effects of diet supplementation with VA on health parameters have yet to be defined.

The objective of the overall research project will be to test the hypothesis that the ingestion of high doses of naturally occurring VA does not cause the adverse lipid and lipoprotein effects known to occur with the consumption of man made trans fatty acids, in particular, elaidic acid (EA). The latter is the primary trans fatty acid found in products such as margarines, cakes, cookies, crackers and other baked and processed foods [Steinhart 2003]. The primary outcome measure will be the ratio of total to high density lipoprotein (HDL) cholesterol. Related secondary outcome measures include concentrations of low density lipoprotein (LDL) cholesterol, HDL cholesterol, triglyceride (TG) and Lp(a). The present proposal is designed to test the feasibility of, and determine the power for, a definitive study.

  Eligibility

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Male
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Male
  • Age >= 18 years
  • Body mass index (BMI) less than 35 kg/m*m
  • Fasting total cholesterol and LDL cholesterol less than the 95% for age and sex
  • Fasting triglyceride <= 400 mg/dl
  • Fasting blood glucose <= 125 mg/dl
  • Fasting thyroid stimulating hormone less than 0.3 or greater than 5.0 uIU/ml
  • Blood pressure <= 150/90
  • Agrees to no alcohol during the study
  • Agrees to maintain same level of physical activity throughout the study

Exclusion Criteria:

  • Smokers
  • Personal history of coronary heart disease, cerebrovascular disease or vascular disease, diabetes, bleeding disorder, liver or renal disease, or of cancer (other than skin cancer) in the last five years.
  • Use of drugs known to affect lipid metabolism, blood thinning agents, or hormones.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00535886

Locations
United States, California
Children's Hospital Oakland Research Institute
Oakland, California, United States, 94609
Sponsors and Collaborators
Children's Hospital & Research Center Oakland
National Cattlemen's Beef Association
Investigators
Principal Investigator: Ronald M Krauss, M.D. Children's Hospital & Research Center Oakland
Study Director: Patty Siri, Ph.D. Children's Hospital & Research Center Oakland
Study Director: Shira Miller, M.D. National Cattlemen's Beef Association
  More Information

Publications:

ClinicalTrials.gov Identifier: NCT00535886     History of Changes
Other Study ID Numbers: MM6222, IRB# 2005-45
Study First Received: September 21, 2007
Last Updated: May 5, 2008
Health Authority: United States: Institutional Review Board

Keywords provided by Children's Hospital & Research Center Oakland:
Trans Fatty Acids
conjugated linoleic acid
vaccenic acid
High Density Lipoprotein Cholesterol
Low Density Lipoprotein Cholesterol
Beef

Additional relevant MeSH terms:
Cardiovascular Diseases
Dyslipidemias
Lipid Metabolism Disorders
Metabolic Diseases

ClinicalTrials.gov processed this record on July 28, 2014