Fish Oil Pills Vs Cod Liver Oil: Which Is the Better Omega-3 Source?


The best source of omega-3 is deep sea fatty fish, which obtain docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) from the smaller fish they eat. You can eat the flesh of the fish itself, but most people prefer taking supplements because they contain concentrated amounts of omega-3 fats. One of the most common questions people have is about the a difference between fish oil pills and cod liver oil. Is there a difference between the two? Which one is a better source of omega-3 fats?

Fish oil and cod liver oil

Let’s take a look at where these two supplements come from. Fish oil is distilled from the tissue of deep-sea fish like salmon, tuna, and mackerel. Cod liver is obtained from the liver of white fish like halibut and cod. Both types contained omega-3 fatty acids DHA and EPA, but in different ratios – the former has a higher EPA to DHA ratio while the latter a higher DHA to EPA ratio.

But the biggest difference between the two is that fish oil contains only EPA and DHA, while cod liver has high amounts of vitamins A and D. They are fat soluble, which that even excess amount gets stored in the liver and tissues. The presence of vitamins A and D in fish liver might place you at risk for an overdose of these two vitamins, especially if you are pregnant.

Safety issues of cod liver oil

Vitamin D is manufactured by the body when it is regularly exposed to sunlight and an overdose is uncommon, even among those who take cod liver oil. What you should be careful about is its vitamin A content. An overdose of vitamin A can cause fatigue, vomiting, and brittle bones and skin. In pregnant women, a dose higher than 10,000 IU per day may increase the risk of birth defects.

Another concern about cod liver supplements is the fact that the liver is where toxins are filtered out. Omega-3 rich fish have the highest concentration of ocean pollutants because of their environment and because they consume smaller fish that may have been exposed to toxins. Even with the best distillation methods, there may still be traces of methylmercury, PCBs, and other toxins in cod liver oil.

The safer source of omega-3s

Although both oils contain DHA and EPA, fish oil pills has twice the amount of total omega-3 fats than cod liver oil. So if your aim is to increase your omega-3 consumption and you are choosing between the two oils, fish oils are the better source, especially for children, pregnant women, and breastfeeding mother. Cod liver oil might be a good alternative to fish oil during the winter months, when the lack of sunlight can place you at risk for a vitamin D deficiency.