Well, I'll give it a stab. To explain why flaxseed oil may not be the best oil, I'll have to try to simply explain eicosanoids.

Eicosanoids are tiny chemical messengers, rather similar in a sense to the hormones insulin and glucagon, except that instead of being produced in a gland, and travelling around to 'service' your cells, eicosanoids are manufactured, used and destroyed, right inside your own cells. Their half-life is way shorter than even insulin and glugagon, so they have been really hard to study, but they have been studied to an extent and apparently the 1982 Nobel Prize was rewarded for research in this field. They've been able to identify over 100 or these little intracellular 'agents'.

What do they do? Well, these little messengers appear to be part of a mechanism for accomplishing a vast number of biochemically mediated processes in our cells, for example, they control and regulate such diverse functions as: blood pressure, blood clotting, inflammatory responses and reactions of the immune system, uterine contractions during birth, pain and fever symptoms in infection (the famous prostaglandin cascade that aspirin will block), constriction and dilatation of the airways and blood vessels and so on.

The production of these little messengers seems to fall into two streams, and in optimum health, it's not all to one direction or another, but a balance. In disease, it seems that the production has been pushed into the Series 2 or 'bad' direction and so you can begin to see symptoms of ill-health manifest.

The good or Series one Eicosanoids---> act as vasodilators, act as immune system enhancers, decrease inflammation, decrease pain, increase oxygen flow, increase endurance, prevent platelet aggregation, dilate airways, decrease cellular proliferation (ie like thickening of arteriole walls leading to hypertension).

The bad or Series two Eicosanoids---> act as vasoconstrictors, act as immune suppressors, increase inflammation, increase pain, decrease oxygen flow..in other words, their effects are pretty much the opposite of the Series one Eicosanoids.

In order to make these little messengers, our cells need lots of the main building block, which is Lineoleic Acid, found in many, many different foods, but particularly rich in animal foods. Getting the lineoleic acid into your cells is controlled by an enzyme called delta-6-saturase according to the Eades. Getting lots of dietary protein, enhances the function of that enzyme in order to get lots of the LA into your cells to be used, while there are several things that impede that enzyme including aging, stress, disease, transfatty acids, dietary alpha lineoleic acid and, a high carbohydrate diet.

So, basically, taking into your body something with very high level of alpha linoleic acid, is like blocking the flow to your cells of the important substance they need to make eicosanoids, the GOOD, as well as the bad. Sort of like cutting down or off the flow of gas or oxygen to your engine see?

Once the lineoleic acid does get inside your cells, there is another enzyme which determines to which extent you'll make good as opposed to bad, and that enzyme is influenced most by insulin and glugagon. Increased insulin, makes the cascade go toward the 'bad' ecosanoids, while glucagon (and the fish oils) tend to push the production more toward the good eicosanoid manufacture.

I hope that helps But the Eades do a really great job of explaining this really clearly, and if you have a chance to pick up a paperback copy, or maybe borrow it from a library even, it's really worth the read.