Influence of the Background Diet on Metabolism of Land-based n-3 PUFA

NCT ID: NCT03558776

Last Updated: 2019-03-07

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 148 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2018-03-13
• Study Completion Date: 2018-12-31

Brief Summary

KoALA study - assessment of the influence of the background diet on the metabolism and the bioavailability of plant n-3 PUFA from linseed oil.

In particular, the study design focusses on the impact of variations in the background diet as confounding factor (e.g. variations in concurrently intake of linoleic acid (n-6)). Further, the influence of a regular intake of milk fat, in particular from free-grazing ruminants, on n-3 PUFA metabolism will be investigated.

Detailed Description

The KoALA study focuses on the impact of variations in the background diet as a confounding factor. The intake of linoleic acid (LA, C18:2 n-6) has been suggested to diminish the metabolism of α-linolenic acid (ALA, C18:3 n-3) to eicosapentaenoic acid (EPA, C20:5 n-3) and docosahexaenoic acid (DHA, 22:6 n-3).

In this context, the proposed study will be conducted to evaluate the influence of the background diet, in particular the impact of the simultaneous intake of LA on the conversion of ALA into their long-chain (LC) metabolites, the incorporation of n-3 LC-PUFA in human tissues and their metabolism into eicosanoids and docosanoids. Further, the influence of a regular intake of milk fat, in particular from free-grazing ruminants, on n-3 PUFA metabolism will be investigated, because short- and middle-chain fatty acids as well as the branched-chain fatty acids in milk fat may influence the conversion of ALA into n-3 LC-PUFA (hypothesis).

Thus, validated nutrition concepts for increasing n-3 LC-PUFA status from plant sources will be developed to ensure an adequate intake of n-3 PUFA according to the guidelines of nutritional societies and as a contribution to the prevention of cardiovascular diseases.

Conditions

Endogenous Conversion of Alpha Linolenic Acid

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: NONE

Study Groups

Linseed oil plus defined background diet (high linolec acid)

Linseed oil (LO) plus daily menu plans (total dietary fat intake: 30 En%): 10 En% LO plus menu plan with 20 En% fat: A) 7 ± 2 En% linoleic acid (n = 37)

Group Type: ACTIVE_COMPARATOR

linseed oil

Intervention Type: DIETARY_SUPPLEMENT

linseed oil and defined background diet

Linseed oil plus defined background diet (low linolec acid)

Linseed oil (LO) plus daily menu plans (total dietary fat intake: 30 En%): 10 En% LO plus menu plan with 20 En% fat: B) \< 2.5 En% linoleic acid (n = 37)

Group Type: ACTIVE_COMPARATOR

linseed oil

Intervention Type: DIETARY_SUPPLEMENT

linseed oil and defined background diet

Linseed oil plus defined background diet (high milk)

Linseed oil (LO) plus daily menu plans (total dietary fat intake: 30 En%): 10 En% LO plus menu plan with 20 En% fat: C) 15 ± 2 En% milk fat (n = 37)

Group Type: ACTIVE_COMPARATOR

linseed oil

Intervention Type: DIETARY_SUPPLEMENT

linseed oil and defined background diet

Linseed oil without defined background diet

Linseed oil (LO) without defined menu plans (D) Western diet, n = 37)

Group Type: PLACEBO_COMPARATOR

linseed oil

Intervention Type: DIETARY_SUPPLEMENT

linseed oil and defined background diet

Interventions

linseed oil

linseed oil and defined background diet

Intervention Type: DIETARY_SUPPLEMENT

Eligibility Criteria

Inclusion Criteria

• Females (in the menopause) and males (50 % each); age: 40 - 65 years; BMI < 30 kg/m2
• Subjects must be able and willing to give written informed consent, and to comply with study procedures
• Subjects with moderate elevated LDL cholesterol (> 3 mmol/l), without lipid-lowering medication
• Persons who consume a traditional "Western diet" composed of meat, sausage, dairy products, cereals, vegetables, fruits etc.
• Precondition: stable eating habits at least one year before enrollment
• Subjects must have adequate fluency in the German language to complete the questionnaires and understand the daily menu plans
• No antihypertensive medication or stable dose for >3 months prior to start of the study and during the entire study period

Exclusion Criteria

• Subjects with any acute or chronic disease (tumor, infection, other), gastrointestinal diseases, diabe-tes mellitus (type I and II), chronic renal disease, diseases of the parathyroids, diseases necessitat-ing regular phlebotomies other chronic diseases which could affect the results of the present study
• Use of medication which could affect the results of the present study including systemic glucocorti-coids, lipid-lowering medication
• Hormone replacement therapy
• Use of dietary supplements, incl. multivitamins, fish oil capsules, minerals, and trace elements (three months before and during the entire study period)
• Weight loss or weight gain (> 3 kg) during the last three months before study begin
• Relevant food allergies (e.g. milk, nuts etc.)
• Pregnancy or lactation
• Transfusion of blood in the last three months before blood sample taking

• Minimum Eligible Age: 40 Years
• Maximum Eligible Age: 65 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

University of Jena

OTHER

Sponsor Role: lead

Responsible Party

Christine Dawczynski,PhD

Leader of the Junior Research Group Nutritional Concepts

Responsibility Role: PRINCIPAL_INVESTIGATOR

Locations

Friedrich-Schiller-University

Jena, Thuringia, Germany

Countries

Germany

Other Identifiers

H6_18

Identifier Type: -

Identifier Source: org_study_id