Homo sapiens (humans) have been consuming fish for tens of thousands of years. By staying close to freshwater and coastal regions, they consistently ate the local fish for sustenance. Compared to our ancestors, we consume far less fish and it shows. Fish oil supplements are common replacements of fatty acids called EPA and DHA, which both have roles in maintaining cognitive function.
Within fish oil, the EPA and DHA are called omega-3 fatty acids and help to reduce inflammation and act as a neuroprotective agent . These omega-3 fatty acids in fish oil are a popular supplement among beginners and enthusiasts because of anti-anxiety effects , improved blood flow to the brain , enhanced memory , and a host of other advantages.
Some of the most interesting and impactful benefits of fish oil come from long-term use rather than single doses. Finally, due to the interest in this natural omega-3 supplement, you will find hundreds of different studies and citations on EPA, DHA, and fish oil. Their uses are various, plentiful, and far reaching.
Also Known As
Eicosapentaenoic Acid, EPA, Docosahexaenoic Acid, DHA, Omega-3 fatty acids, Omega-3, Omega 3, N-3 Fatty Acids
Editors’ Thoughts on Fish Oil
Fish oil is probably the only nootropic or cognitive enhancer that I am willing to take every single day and I do so with blind faith. That says a lot as I am usually quite cautious and restrictive about what I am taking.
With two PhDs for parents, supplementation comes with greater scrutiny for scientific evidence. While I feel comfortable taking almost anything once, long-term usage is much harder for me to justify except in the case of fish oil.
I would be lying if I said that fish oil has significantly altered my brain in any noticeable way. The reality is, I have not really dedicated enough time or research to determine whether fish oil has had any real impact on changing the way my brain operates or feels.
However, I have such a high opinion of the long-term effects of fish oil (for both my brain and body), that I feel completely comfortable taking it daily and recommending it to others. As a final note, because of the bioavailability and additional benefits, I use krill oil rather than normal fish oil.
Benefits of Fish Oil
As with any well-researched compound, the evidence regarding fish oil is quite conclusive. While each of the benefits of fish oil vary in their degree of scientific research, it is clearly a drug that has significant positive effects.
Fish Oil, Neuroprotection, and Anti-Inflammation
Reducing inflammation is an important role for supplements in both the brain and the body. With fish oil, DHA acts as a precursor to a compound called NPD1, which is an anti-inflammatory agent that acts as a neuroprotective as well. EPA has anti-inflammatory and vasodilatory effects as well . The brain suffers from inflammation due to many common stressors including things like excess sugar, gluten (in some), and stress.
These neuroprotective effects are paired with others, which help to mitigate many of the early stages of Alzheimer’s disease . EPA and DHA, paired with other compounds like choline and uridine monophosphate, can significantly impact synapse formation in the brain .
Mood, Memory, and Cognition Benefits
One major benefit of fish oil is for anxiety and depression. There are over 23 studies on the notable fish oil benefits related to depression, but one meta-analysis looked over 15 different studies including around 1,000 participants. This large cohort analysis concluded that fish oil (and EPA specifically) was important for reducing symptoms of depression .
Another study looked at how fish oil could reduce feelings of anxiety by 20% in medical students who were taking around 2500 mg of omega-3 fish oil . Beyond benefits related to mood, early research suggests memory enhancement as well . Through increased cerebral oxygenation and blood flow, higher doses of fish oil can prevent cognitive decline as well .
These and approximately 70+ other benefits of fish oil are well-studied and documented in the scientific literature.
How Does Fish Oil Work?
Fish oil works in a number of different ways to impact brain health. For one, fish oil is filled with the same fatty acids that the brain is made of. Because nearly 60% of the human brain is fat, omega-3 fatty acids help replace what is lost . Many of the cognitive advantages, such as memory, preventing cognitive decline, etc., are related to increased oxygenation and blood flow to the brain.
Another fish oil mechanism of action is to balance the omega-3 and omega-6 fatty acids within cells. By balancing the ratio of omega-3 and 6 fatty acids, it helps to reduce inflammation . The standard American diet is usually a ratio of 1:15-20 (15 – 20 times as much omega-6 fatty acids than omega-3). This leads to a whole host of cognitive (and physical) health problems that omega-3 supplementation can halt and reverse.
Finally, the omega-3 fatty acids can act as precursors (raw materials) for the body and brain to produce positive compounds. One of these is called NPD1, which is a neuroprotective agent derived from DHA .
Side Effects of Fish Oil
Fish oil side effects are both rare and mild. There are very few reports of toxicity or overdoses and most of the concerns regarding fish oil are about mercury in the fish-based supplements. The conclusion amongst many researchers is that most fish oil supplements are free from dangerous levels of mercury .
It seems that cod liver oil, sardine oil, and mackerel oil are all good sources of fish oil because they are non-predatory fish. Finally, krill oil supplements are considered low in mercury as well.
Other unintended side effects of fish oil (which turn out to be more like benefits) are increased EPA levels within the skin. This causes a reduced risk of sunburns and in one study, fish oil increased the amount of sun required for a sunburn by 37 – 117% .
Fish Oil Dosage Recommendations
The fish oil dosage recommendations will depend highly upon the goals for your supplementation. If you buy fish oil for the purpose of general health (both cognitive and physical), then you can get away with a mixed dosage of 250 mg. However, the American Heart Association sees such benefits of fish oil that they recommend 1 gram (1000 mg) daily.
Up to 6 grams per day is recommended for muscle soreness and related aches and pains. For most cognitive enhancement and neuroprotection, a starting dosage of around 1000 mg DHA and 500 mg EPA will be sufficient.
How and Where to Buy Fish Oil
Finding a fish oil supplement for sale is not difficult and comes with plenty of options both in local brick and mortar locations and online. One important note to keep in mind is that many fish oil supplements have generic omega-3 fatty acids and not a high volume of EPA and DHA. These are by far the two most important omega-3 fatty acids that are in fish oil. Everything else is nice, but extraneous. Ensure you find a supplement with predominantly EPA and DHA.
Another common mistake some people make is to overlook the dosage recommendations when gauging price. Some fish oil supplements will say they have 90 servings, but the dosage they recommend is half what you will use (meaning it is only 45 servings). Most of your work with fish oil research will be to find out which product makes the most sense for your money.
However, there is a way to buy fish oil that is more bioavailable and better absorbed than most. People that buy krill oil find it to be an effective way of supplementing DHA and EPA without higher doses. Krill oil benefits are many including more absorption and an additional compound called astaxanthin. There are also benefits of krill oil for pregnant women to avoid high doses of mercury while about to conceive.
Finally, keep in mind that omega-3 fatty acids do not automatically mean they are fish oil or DHA and EPA. Many omega-3 supplements (especially the vegan ones) are filled with ALA (alpha lipoic acid), which is not well converted into DHA and EPA as the human brain needs.
Selected Community Experiences
“Im really curious why Im terrible at recalling things, learning, reading books and studying in general when I don't take fish oil. I just cannot do any brain related activities. Everytime I stop taking it eventually I find myself having a hard time thinking or doing some hard mental activities. Even coffee doesnt help.”  – Dalai_Fapa
“I was ingesting 4.6g of EPA/DHA every day for a month for joint issues and brain health. For that month, I was also the most anxious I had been in a long time. So I analyzed what I had changed in my routine and realized the source of my anxiety could have been the fish oil supplementation. It's been a week since I stopped and I feel back to my happy, normal self.”  – Elwaytime7
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