Bottomline:  Study demonstrates an increased conversion of the omega-6 fat, linoleic acid to arachidonic acid a potent omega-6 fat in cystic fibrosis cells, which may be what drives chronic inflammation. Adding DHA reversed the problem.

Summary:  Decreased levels of linoleic acid and DHA are associated with cystic fibrosis patients. Researchers sought to determine the mechanism for this aberration and also looked at the impact of adding DHA to cultured airway cells resembling cystic fibrosis.  They found that the airway cells draw on the linoleic acid to make more arachidonic acid, the potent omega-6 fat, which makes several types of inflammatory eicosanoids.  Notably, this defect was corrected by adding DHA.

The researchers concluded that DHA is a potential candidate to dampen the chronic inflammatory response in cystic fibrosis patients as it down-regulates the production of arachidonic acid-derived inflammatory eicosanoids.

Quote: “Aggressive supplementation with linoleic acid may…lead to an increased inflammatory response as a result of its extensive metabolism to arachidonate and inflammatory eicosanoids.”

Comment: It would be interesting to conduct an intervention study similar on cystic fibrosis patients, in which they all would be supplemented with DHA, and then either put on a low-omega-6 fat diet or a classic western diet (which is high in omega-6 fat).

Link to Study:
Al-turkmani MR et al. A mechanism accounting for the low cellular level of linoleic acid in cystic fibrosis and its reversal by DHA. Journal of Lipid Research, Vol. 49, 1946-1954, September 2008.

Abbreviations & Notes:

• Arachidonic acid/arachidonate is the potent omega-6 fat, found in animal foods

• DHA is a potent omega-3 fat, found in fish and fish oil

• Linoleic acid is the omega-6 fat found in vegetable oils such as: soybean oil, cottonseed oil and corn oil