Both krill oil and fish oil are good sources of omega-3 essential fatty acids, which we know are important for many aspects of human health. However, krill oil also contains some important additional nutrients that may make it more effective than fish oil alone.
First, it is important to realize that the omega-3s in fish oil come in the form of triglycerides – three fatty acids on a single backbone. Triglycerides hold a lot of energy – more than carbs or proteins. But they can’t pass through cell membranes easily. Therefore, they must be broken down by the liver into their components before being absorbed by the body. High levels of triglycerides are associated with vascular disease, heart disease and stroke.
Krill oil contains phospholipid based omega-3s, which are readily absorbed in the intestines and recognized by our cell walls as belonging in the body – no reprocessing necessary. Therefore, the omega-3s in krill oil are taken up in the body more efficiently than those in fish oil.
In addition, krill oil contains astaxanthin, a powerful anti-oxidant missing in fish oil, which scavenges free radicals in the body, and is great for vision and eye health.
So to summarize, fish oil and krill oil both contain the essential fatty acids EPA and DHA, but krill oil also contain phospholipids, astaxanthin and choline. Fish oil is not as easily absorbed by the body, because it contains triglycerides, which must be processed before being absorbed. Krill oil can be taken up by the body with no reprocessing.