Are Omega-6 Fats Inflammation Antagonists or Not?
The origin of the pro-inflammatory/n-6 connection can be traced back to fatty acid biochemistry and their role in the production of PGE2, an eicosanoid (a short-lived hormone-like compound) that has pro-inflammatory actions. As shown in the image, linoleic acid (soybean oil, corn oil, but also nuts and seeds) and arachidonic acid (eggs and meat) can both be converted to PGE2. That makes sense. But does it really happen?
Not really. In fact, very small amounts of dietary linoleic acid ever get converted to arachidonic acid. The bottom line is that the conversion of linoleic acid to arachidonic acid and then to PGE2 is not as clear-cut as we would like it to be.

It's also not the most efficient biochemical pathway.
Both the linoleic acid and alpha-linolenic acid conversion pathways are limited by the Delta-6-desaturase (D6D) enzyme. They both compete for this enzyme's "attention" and alpha-linolenic acid actually has a higher affinity for D6D. So all things being equal, the D6D enzyme would rather act on alpha-linolenic acid not linoleic acid.
Now if that linoleic acid eventually does get converted to arachidonic acid you'd be in trouble, right? Your joints would probably catch on fire, you'd get inflammatory bowel disease, and rapidly start developing dementia.
Not quite.

In fact, arachidonic acid plays an extremely important role in the body. As Dr. Jeff Volek pointed out to me a couple months ago, arachidonic acid is one of the two main fatty acids that infant formulas are fortified with (the other being DHA). The body also seems to tightly regulate and conserve arachidonic acid levels. It also stimulates Testosterone production.
So clearly it has to have some benefits.

The Truth About Inflammation

Let's explore the anti-inflammatory effects of omega-6 fats and emerging research that has uncovered the most powerful role of omega-6 fats in the diet. Here are some findings from two studies to help summarize the lack of pro-inflammatory effects from omega-6 fats.
• A study of 1300 men and women examined the relationship between plasma fatty acid levels and circulating inflammatory markers. Individuals with the highest levels of linoleic acid had the highest levels of the inflammatory cytokins TNF-α and IL-6. (Ferrecci et al; J Clin Endocrinol Metab 2006)
• In the same study the people with the highest plasma arachidonic acid levels also had the lowest IL-6 levels. (Ferrecci et al; J Clin Endocrinol Metab, 2006)
• A study that looked at the effects of decrease linoleic acid intake from 12% to 4% of calories yielded no change in inflammatory markers IL-6 or C-Reactive Protein. (Liou et al; J Nutr, 2007)

Anti-Inflammatory Omega-6 Fats

With all the talk about corn oil, inflammation, and arachidonic acid, one omega-6 fat is always passed over: Gamma-Linolenic Acid, or GLA.
One of the main reasons GLA is overlooked may be due to the fact that it's damn near impossible to get it in our diets. I mean, when was the last time you doused your salad with borage seed oil or evening primrose oil?
Luckily, you can make it easy (and more palatable) to get your GLA by taking Biotest's new FA3 supplement.
But why should you take GLA? Because it can be converted to the anti-inflammatory eiscosaoid PGE1.This isn't just biochemical mumbo jumbo talk; it really has anti-inflammatory action.
I find it interesting that there isn't a large body of research looking at the effects of GLA (apparently the Evening Primrose Council isn't funding a lot of research), but here are findings from several of the GLA studies that have been completed:
• Daily supplementation with Evening Primrose oil reduces symptoms of atopic dermatitis. (Andreassi et al; J Int Med Res, 1997 & Senapati et al; Indian J Dermatol Venereol Leprol, 2009 & Hederos et al; Arch Dis Child, 1996)
• 1.5 g/d of GLA significantly reduced leukotriene production after just one week (thereby reducing inflammation). (Surette et al; Clin Therapeutics, 2003)
• 1.8g/d of GLA has been shown to improve arthritis pain by reducing the number of tender and swollen joints. (Leventhal et al; Ann Intern Med)
• GLA has been shown to reduce tumor growth. (Serini et al; Apoptosis, 2009)

Omega- 6 Fats — Inflammation Clean Up Crew

Another interesting point regarding arachidonic acid is that it has a biochemical fate that we didn't know about until just a few years ago. (Many people still have never heard of about this.)
Arachidonic acid can also be converted to a new class of compounds called Lipoxins and Resolvins. Theses compounds are called "novel lipid mediators." What's interesting is that they don't stop inflammation, but help clean up the mess left by inflammation like a janitor at your local high school.
Fighting, controlling, and preventing inflammation has become a major focus in research and our health care system, but scientists are just now starting to appreciate the fact that preventing inflammation may not be the best course of action. We also need to accelerate the clean-up and renewal from inflammation. Resolvins and lipoxins do just that.

One Final Point on Good vs. Bad Fats

More research is looking at the effects of fatty acids on health, and it's becoming clear that the omega-6 = bad mantra is naive and flawed.
Here's one last example to illustrate this point: a recent study was completed with the goal of seeing if a person's fatty acid profile could predict their ten-year risk of developing heart disease better than the current standard Frammingham Risk Score.
It turns out that it does. Do you know what fatty acid carried the most weight? You guessed it: linoleic acid, an omega-6 fat.
In fact, of the eight fatty acids that surfaced as being beneficial in this analysis, three were omega-6 fats and only one was an omega-3 fat.
Now how do you like them apples?
So start taking some GLA and hop off the Omega-6 hatin' train. You'll be doing your body a favor.