Augmentation of long chain polyunsaturated omega 3 fatty acid (LCPUFA omega
3) status can be reached by consumption of fish oil or by improvement of t
he conversion of a-linolenic acid (ALA) to LCPUFA omega 3. Since gamma-lino
lenic acid (GLA) might activate the rate-limiting Delta-6 desaturation, we
investigated whether GLA augments LCPUFA omega 3 status. Eight adults recei
ved 1.4 g GLA for 4 weeks and subsequently 2.2 g ALA+1.4 g GLA daily during
another 4 weeks. Another seven adults received a daily oral dose of 2.2 g
ALA for 4 weeks, and subsequently 2.2 g ALA+1.4 g GLA during another 4 week
s. ALA, or ALA+GLA, did not significantly augment EPA and DHA contents. We
conclude that the LCPUFA omega 3 status can not be improved by supplementat
ion of low dose GLA, neither by co-supplementation of ALA. Poor conversion
of ALA to LCPUFA omega 3 may be caused by preferential beta-oxidation of AL
A, negative feedback of arachidonic acid from the omnivorous diet, or by th
e low dietary ALA/LA ratio.