Omega-3, 6, and 9 Fatty Acids And The Brain

Omega-3, 6, and 9 fatty acids are all essential for brain health. In addition, they help to regulate moods and may even help protect against age-related memory loss.

However, deficiencies in these fats can contribute to a wide variety of serious disorders, including depression, ADHD, Alzheimer’s disease, and other forms of dementia.

In this article, we will explore the benefits of omega-3, 6, and 9 fatty acids for mental health and how you can incorporate them into your diet safely to reap their many rewards.

Omega-3 Fatty Acids

Omega-3 Fatty Acids (alpha-linoleic acid) are a type of polyunsaturated fat that is essential to human health, but the body cannot make them.

They must be obtained through diet or supplementation. The body can convert ALA into two fatty acids with important roles in the brain:

  1. Docosahexaenoic acid, or DHA,
  2. Eicosapentaenoic acid, or EPA

DHA is a long-chain omega-3 that is most abundant in grey matter of the central nervous system and is the most abundant omega-3 fatty acid in human brain tissue.

DHA comprises about 10% of the total cerebral cortex and more than 15% in the hippocampus, areas involved with learning and memory.

DHA has also been shown to be involved in synaptic plasticity (involved with learning) and membrane fluidity.

EPA & DHA are generally preferred to ALA, although the body can convert both DHA and EPA into their respective metabolites. EPA and DHA have important effects on mood and behavior in humans because they are thought to be involved in neuronal membrane fluidity & receptor density, and neuroprotection (especially for dendrites).

Studies show that low levels of omega-3 (specifically DHA) in the brain may contribute to depression by affecting neurotransmitter levels and functioning. EPA is also thought to play an important role in mood regulation, specifically related to reducing anxiety symptoms.

Some studies have found that patients taking dietary fish oil supplements with a high amount of omega-3 fatty acids had reduced symptoms of depression, anxiety, and bipolar disorder (although results have not been consistent).

Further research is needed to determine whether there are differences between DHA and EPA in children, but current thought is that both nutrients play a role in mood enhancement.

It is also important to remember that omega-3 fatty acids should be consumed with an equal amount of omega-6 fatty acids, but most people consume far more omega-6s than omega-3s. Therefore, it is beneficial to pay attention to the ratio of omega-3 to 6 in the diet.

Foods high in Omega-3s

Foods that contain high concentrations of Omega-3 fatty acids are oily fish like salmon as well as eggs, walnuts, and flax seeds.

It is important to note that the body can convert ALA into EPA, but not as efficiently as if EPA were consumed through diet. Therefore, it is best to consume Omega-3 fatty acids directly instead of ALA.

Omega-6 Fatty Acids

Omega-6 fatty acids are needed for a healthy brain as they are involved in the production of serotonin which is known as the happy chemical because it lifts your mood and helps you relax.

Omega-3s and omega-6s should be consumed in a ratio of approximately 1:1. A diet with excessive amounts of omega-6, such as a typical Western diet with excessive amounts of processed vegetable oils, can lead to too many pro-inflammatory chemicals being produced.

This can result in depressive symptoms and inflammation in the brain and is thought to play a role in Alzheimer’s disease.

Omega 6 fatty acids are found in safflower oil, sunflower oil, corn oil, soybean oil, margarine, animal products, and whole grains.

Foods high in Omega-6

Omega-6 fatty acids are just as essential and beneficial to the body, but they also have a negative reputation when consumed in excess of omega-3 fatty acids.

As previously mentioned, it is important to consume them with an equal ratio of omega 3s because if there are more omega 6’s than 3’s, the omega 6 fatty acids are more likely to be converted to proinflammatory eicosanoids.

Omega-6 fatty acids can be found in safflower oil, sunflower oil, corn oil, and peanut oils.

However, the most common source for omega-6s is vegetable oils & processed foods that contain these oils. Therefore, it is important to read labels and choose foods that are high in Omega-3s like salmon or walnuts instead of vegetable oils when possible.

Omega-9 Fatty Acids

Omega-9 fatty acids, also known as oleic acid, are found in many foods like olive oil and avocados.

Recently people have been finding additional benefits to consuming Omega-9s, including mood enhancement and reduced inflammation.

Omega-3 and 9 fatty acids are found in the highest concentrations in seafood (especially fish), tree nuts, olives, olive oil, avocados, and eggs.

Foods high in Omega-9

Omega-9 fatty acids are found in olive and canola oils, avocados, and nuts.

Although they are considered essential for us to obtain, humans have the ability to synthesize them, so we don’t need to worry about the quantity we eat.

Like omega-6s, they should be consumed in a ratio of approximately 1:1 or 2:1 with omega-3s.

Healthy Omega-Fatty Acid Ratio

The general guideline for omega 6 to 3 ratio is 2:1. In other words, for every 2 grams of omega-6 fatty acids consumed, 1 gram of omega 3 should be as well.

Research also indicates that the optimal ratio can be closer to 4:1 or 3:1 (or even 5:1) in certain situations such as severe depression.

In some cases, excess consumption of Omega-3 can actually be unhealthy, especially if you consume too many omega-3s and not enough Omega-6s.

Research shows that the intake of EPA & DHA must be balanced with Omega 6 fatty acids to maintain health benefits.


Although it is ideal to get all of our nutrients from food, some people believe that supplementation in the form of Omega-3 and Omega-6 fish oil is an effective alternative.

It has been shown that supplementing with omega fatty acids can lead to improvements in mood and cognition.

Omega-3 fatty acids can be found in fish oil, cod liver oil, flaxseed oil, and green leafy vegetables. It is important to consume omega 3 fatty acids from as many sources as possible because they have different effects on the body.

For example, fish oil is non-acidic and more easily digested, while flaxseed oil contains an essential fatty acid called Alpha-Linolenic Acid (ALA). Although ALA is converted into EPA and DHA in the body, it only produces small amounts of these chemicals.

Another option for Omega-3 fatty acids is krill oil. Krill is a small crustacean that lives in oceans around the world.

It contains omega-3 fatty acid phospholipids, which are more easily absorbed by the body than fish oil and contain astaxanthin.

The latter helps prevent oxidative damage in cells and therefore protects cell membranes, an important function in cognitive health.


Omega 3s and 6s are essential fatty acids that we need to consume because our bodies can’t produce them independently.

They do many things in the body, including regulating inflammation and protecting cells from damage.

However, there is a right ratio for omega-6 to omega-3 consumption. Ideally, it should be 2:1 or slightly higher to maintain health.

If you are concerned with getting the right ratio, eating fatty fish two times a week is suggested. Although supplementation is an option, fish and seeds are more beneficial.

Leave a comment

Your email address will not be published.