This is where I will start to explain the differences in the variations of supplements. With so many variations this is why we must talk to our doctors so we are sure we are getting the correct levels of the Omega 3 fatty acids. Medications and other supplements we take can have a reaction. If you take a daily vitamin you have to watch which sources of Omega 3 fatty acids you consume.
One of the more popular supplements is the use of regular fish oil. Fish oil is a capsule filled with fish oil. Usually the fish oil they use is from mackerel or sardines since they are a naturally oily fish. The capsules do tend to have a fishy smell and after taste. They also tend to be of the larger variety of pill which can be hard for some to swallow properly. Fish oil from these sources can sometimes have an adverse reaction to some medications used in auto immune disorders.
Another popular supplement is Krill oil which comes from the Krill fish.
This is also a capsule that is filled with Krill oil. Krill fish are also naturally oily and are also full of DHA and EPA fatty acids. One of the reasons Krill oil is so popular is that the capsules are smaller to swallow. They also lack the fishy smell and after that the other fish oil capsules tend to have. This supplement can interact with some medications causing them to go inactive.
A supplement that is considered for the vegetarian and vegan diets is algae capsules. The capsules contain all of the Omega 3 fatty acids, it is one of the only sources that contains all three without being from a fish. The type of algae they use is dried and ground into powder before being put into the capsules. They can create an allergic reaction to those unable to touch algae.
Vegetarian and vegans can also take the ALA natural sources. The issue is that many do not eat fish due to their diet restrictions. This means the need to find alternate sources for the DHA and EPA naturally found in fish. They must also be careful how they handle the sources with ALA. Since the ingredients can go inactive if the seeds are ground too early. Also allowing nuts to go stale will diminish the Omega 3 fatty acids.
Cod liver oil is another supplement that has been around for centuries. It has been used for things like constipation. Since it is made from the liver of the cod fish it does taste fishy and have the after taste. You can buy this as oil you take off a spoon or capsules. They do tend to be on the larger side which makes them harder to swallow. Do talk to your doctor about the correct dosage when using the spoon method.
With all supplements you want to be sure they are from a source that does not have heavy metal poisoning issues. Even supplements can have mercury, lead and cadmium. All of these heavy metals will may you extremely sick. Pregnant women need to avoid heavy metals at all costs since it will harm the fetus.