From the
Sherdogger's Guide To Fish Oil Supplementation in the FAQ:
Are There Dangers With Fish Oil?
Generally speaking, no. But there are a few concerns people need to be aware of. One is possible rancidity of fish oil, and the side effect of blood thinning.
Rancidity: - While the benefits of fish oil can't be refuted, on the flip side is spoiled, or rancid fish oil. Being a highly unsaturated fat, fish oil is extremely vulnerable to oxidation; this is the reason the fish in your fridge is only good for a few days, max. Free radicals LOVE unsaturated fatty acids, just like your 18 year old cousin LOVES going across the border to Tijuana to get hammered. It's not a good thing, and it's kinda scary.
When fish oil become rancid, it becomes a
lipid peroxide; this turns a potentially helpful supplement into a harmful one. That last thing we need to do as athletes is add to our free radical load, especially with peroxides. So how does one avoid this? A number of ways:
- Make sure the fish oil capsules you buy are of quality, and properly foil-sealed when you first open it.
- Make sure the liquid fish oil you buy is in an opaque GLASS bottle and properly sealed when you first open it.
- Put your fish oil in the fridge; with capsules, another option is to place them in the freezer. This will prolong the shelf life, as well as prevent oxidation.
- Bite into your fish oil capsules. Yes, I mean it. This is tell you exactly how fresh your capsules are, and if they are rancid, you will know it right away. Fresh fish oil will be clear, particulate-free, and tastes mildly fishy, as one would expect. Rancid fish oil tastes like licking the bottom of a garbage dumpster in central New York. Biting into capsules is recommended by the highly respected Dr Michael Eades, author of Protein Power, and our very own and highly respected poster Sonny.
There's also been some studies done regarding fish oil intake and vitamin E; because of the potential for fish oil to oxidize, even in the blood, some have suggested that vitamin E be ingested along with fish oil. Other studies have shown a synergistic (enhanced) effect, and even others have shown a decrease in blood levels of vitamin E. Many manufacturers will combined fish oil and vitamin E to act as a preservative, so this may be a completely moot point.
