Trial to Assess the Effects of Different Trans-fatty Acids on Endothelial Function in Humans

Summary

The aim of the study is to compare a diet rich in trans fatty acids (TFA) from ruminant sources with a diet rich in TFA from hydrogenated vegetable oils (PHVO) in regard to their effects on cardiovascular risk markers (endothelial function, blood lipids, inflammation and coagulation parameters in the blood).

After a two week run-in period (diet without TFA) volunteers are randomized into three groups with different diets: diet rich in TFA from ruminant sources, diet rich in TFA from PHVO and diet without TFA. The intervention period lasts four weeks.

A nutritionist introduces the basic issues of the study diets. All volunteers supply themselves according to the recommendations of the Swiss food pyramid. Fat free food can be chosen individually in the context of defined guidelines. The amount and source of the fat in the diet are strictly defined. During the whole study, volunteers meet the nutritionist every 2 weeks, and in the weeks between, the volunteers are contacted by phone.

The volunteers will continue their normal daily life and physical activities. At the beginning of the run-in period and at the beginning and the end of the intervention period the endothelial function of the brachial artery will be assessed using flow-mediated dilation (FMD)/nitro-mediated dilation (NMD) methods and blood samples will be collected to analyze blood lipids, inflammation and coagulation parameters in the blood.

Hypothesis:

1. Diet enriched with ruminant TFA has not the same negative effect on cardiovascular risk markers as diet enriched with the same amount of industrial TFA compared with a diet without TFA.
2. Diet enriched with ruminant TFA has not a more negative effect on cardiovascular risk markers as diet without TFA.

Conditions

• Healthy

Interventions

DIETARY_SUPPLEMENT

diet enriched with industrial trans fatty acids

After run-in phase of 2 weeks with margarine without TFA, 4 weeks with margarine enriched with industrial trans fatty acids following. TFA-percentage of total energy consumption is 2% or 6% of total fat energy consumption.

DIETARY_SUPPLEMENT

diet enriched with ruminant trans fatty acids

After run-in phase of 2 weeks with margarine without TFA, 4 weeks with butter enriched with ruminant trans fatty acids following. TFA-percentage of total energy consumption is 2% or 6% of total fat energy consumption.

DIETARY_SUPPLEMENT

diet without any trans fatty acids

6 weeks with margarine without any trans fatty acids.

Sponsors & Collaborators

• Agroscope Liebefeld-Posieux Research Station ALP

  collaborator OTHER

• University of Bern

  collaborator OTHER

• Schweizerische Herzstiftung

  collaborator OTHER

• Bundesamt für Landwirtschaft

  collaborator UNKNOWN

• Emmi Schweiz AG

  collaborator UNKNOWN

• Insel Gruppe AG, University Hospital Bern

  lead OTHER

Principal Investigators

• Hugo Saner, Prof. Dr. med · Cardiovascular Prevention and Rehabilitation, University Hospital Bern, Switzerland

• Alexandra Schmid, Dipl. oec. troph. · Agroscope Liebefeld-Posieux Research Station ALP, Posieux, Switzerland

• Thomas Radtke, MSc · Cardiovascular Prevention and Rehabilitation, University Hospital Bern, Switzerland

Study Design

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

QUADRUPLE

Model

PARALLEL

Eligibility

Min Age

45 Years

Max Age

69 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2009-07-31

Primary Completion

2013-06-30

Completion

2013-06-30

Countries

• Switzerland

Study Locations