Supplementation of Alpha-linolenic Acid (ALA)-Rich Oil in Humans

N-3 PUFA are important for human health and nutrition. Unfortunately, the land-based n-3 ALA is a limited precursor for the formation of n-3 LC-PUFA. The conversion of ALA depends on the rate-limiting ∆6-desaturation.

The first objective of this study is to investigate differences of the accumulation of n-3 LC-PUFA (EPA, DPA and DHA) in human lipids during supplementation of ALA-rich linseed oil dependent on age, gender and physiological conditions (overweight, increased serum total cholesterol). One study group will receive fish oil with mainly EPA as positive control.

The second objective is to compare the n-3 LC-PUFA enrichment during the linseed oil supplementation (study LSEP H50-KK) with the n-3 LC-PUFA enrichment during the further Echium oil supplementation (study LSEP H42-KK). The second study will be the control for the first study.

Therefore, it is planned to recruit the same subjects for the linseed oil supplementation.

Eighty volunteers will be recruited and allocated into four study groups depending on age and BMI. Three groups (each n=20) will receive daily ca. 15 g linseed oil (mean age: 25 and 55 years; mean BMI < 25; and mean age 55 and BMI > 25). One group (n=20) will receive n-3PUFA free olive oil (mean age 25 and 55, BMI < 25). The double-blind, randomized, parallel-designed study will start with a two-weeks run-in period, followed by an eight-weeks supplementation period. After the run-in period, one week and eight weeks of oil supplementation blood will be drawn and 24-h urine will be sampled.

Altogether, the fatty acid distribution after Echium oil and linseed oil supplementation from similar subjects can be statistically analysed.

Inclusion criteria

• healthy subjects

Exclusion criteria

• cholesterol lowering drugs
• chronic diseases
• pregnancy, lactation
• intake of nutritional supplements