Influence of the Background Diet on Metabolism of Land-based n-3 PUFA From Linseed Oil - Focus: Conversion of Alpha Linolenic Acid (ALA; KoALA Study)
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 148
- 试验地点
- 1
- 主要终点
- Percentage of EPA and further n-3 PUFA in plasma and erythrocyte lipids
研究概览
简要总结
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.
详细描述
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.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- None
入排标准
- 年龄范围
- 40 Years 至 65 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Whether participants meet the inclusion criteria will be evaluated by screening prior the run-in (blood sampling).
- •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
排除标准
- •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
研究组 & 干预措施
Linseed oil without defined background diet
Linseed oil (LO) without defined menu plans (D) Western diet, n = 37)
干预措施: linseed oil (Dietary Supplement)
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)
干预措施: linseed oil (Dietary Supplement)
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)
干预措施: linseed oil (Dietary Supplement)
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)
干预措施: linseed oil (Dietary Supplement)
结局指标
主要结局
Percentage of EPA and further n-3 PUFA in plasma and erythrocyte lipids
时间窗: change from baseline after 4, 8 and 12 weeks
Percentage of EPA and further n-3 PUFA (ALA, DPA, DHA) in plasma and erythrocyte lipids (available from the gas chromatographic analysis)
次要结局
- Diabetes risk markers(change from baseline after 4, 8 and 12 weeks)
- Fatty acid distribution in plasma lipids(change from baseline after 4, 8 and 12 weeks)
- Unbound free fatty acid profiles in plasma(change from baseline after 12 weeks)
- Blood lipids(change from baseline after 4, 8 and 12 weeks)
- Inflammatory markers(change from baseline after 4, 8 and 12 weeks)
- Cardiovascular risk factors(change from baseline after 4, 8 and 12 weeks)
- Futher biomarkers (cardovascular risk factors)(change from baseline after 12 weeks)
- Fatty acid distribution in erythrocyte lipids(change from baseline after 4, 8 and 12 weeks)
- Anthropometric and physiological data(change from baseline after 4, 8 and 12 weeks)
- Clotting markers(change from baseline after 4, 8 and 12 weeks)
研究者
Christine Dawczynski,PhD
Leader of the Junior Research Group Nutritional Concepts
University of Jena