Krill oil contains Astaxanthin which is an antioxidant that apparently protects the oil from going rancid (whether it still goes rancid inside the body I don't know).... It is found in many red coloured fish (salmon), lobsters and shrimps (you see it when they turn red when boiled).
Astaxanthin - Wikipedia, the free encyclopedia
I did eat a package of krill oil pills last summer because I read the astaxanthin in it help protect the body from getting a sunburn. But from now on I think I will just eat shrimps since I'm not a whale. I don't want to supplement with too many things but rather eat a variety of healthy foods
Take a walk on the wild side.