For those of you that are crazy enough to read what I post :
I have always said that if you supplement with Fish Oil that you need to protect the double bonds of the fish oil from oxidation (peroxidation) with Vit E (or other antioxidants).
Here are excerpts from a new article that supports my view concerning this.

Dietary omega-3 fatty acids. Lack of antioxidants?
American Journal of Clinical Nutrition
August 2011; Vol. 94; No. 2; pp. 618-619
Bjarne Osterud
This author cites evidence that increased intake of dietary omega-3 fatty
acids may increase the risks of peroxidation

“Intake of omega-3 fatty acids may not always be beneficial because
incorporation of these polyunsaturated fatty acids (PUFAs) in the cell membranes makes the cells more susceptible to oxidation if there is a lack of antioxidants where the omega-3 fatty acids are present in the membranes.”
“Contrary to an anti-inflammatory effect, PUFAs may cause oxidative stress
whereby the production of pro-inflammatory products is enhanced.”
“Everywhere where PUFAs are present in live, natural material, there is always an excess of antioxidants, which are removed when the omega-3 fatty acids are refined or when they are isolated. This means that these fatty acids when taken as dietary supplements may cause severe oxidation in their local environment in which support of antioxidants may be quite low. Omega-3 fatty acids may thereby cause oxidative stress and subsequently an increase in pro-inflammatory products.”
The lack proinflamatory agents in native Greenlanders despite their high intakes of omega-3 fatty acids in their diet through seal and whale blubber may be credited to the fact that “their diet is also rich in natural antioxidants associated with omega-3 fatty acids contained in blubber.”
Thus, antioxidants may be required for the anti-inflammatory and other benefits of
omega-3 fatty acids.



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Usually the amount of Vit E contained in most fish oils isn't near enough. They usually only put in enough to protect the oil from oxidation while it's in the bottle. This is usually in the 10 iu to 15 iu range. It takes 100 iu Vit E per 600 mg to 1200 mg of fish oil once it's in the dog.
The amount of Vit E in dog foods is only enough to satisfy the dog's nutritional need and to prevent oxidation of the fats in the dog food while it's in the bag.

Once the fish oil or food oil is inside the dog, much larger amounts are needed.



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