Omega Fatty Acids: 3, 6, and 9 Explained

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What are Omega Fatty Acids?

Omega-3, -6, and -9 fatty acids are all important dietary fats that play crucial roles in the human body. There are health benefits associated with all three, but getting the right balance between them is important. An imbalance in the kinds of omega fatty acids in your diet may contribute to a number of chronic diseases.

3, 6, and 9: What are the differences?

The primary difference between omega-3, omega-6, and omega-9 fatty acids lies in their chemical structure, particularly the position of the first double bond from the omega (ω) end of the fatty acid chain (See Figure 1, below). The placement of these double bonds changes how our bodies use them.

Omega-3 and omega-6 are essential fats, meaning they must be obtained from the diet. Omega-3s, found in foods like fish, flaxseeds, and walnuts, are known for their anti-inflammatory properties. Omega-6s, are found in vegetable oils and certain processed foods. Omega-9s are technically non-essential (since the body can produce them) but can be found in foods like olive oil and avocados. Omega fatty acids are classified based on how far their first double bond is from the omega (ω) end of the fatty acid.

Health Impacts

While all three kinds of fatty acids are associated with health benefits, omega-3 fatty acids have gained the most popularity and has been more thoroughly researched than omega-6 and -9 fatty acids.

Omega-3 fatty acid intake has been associated with everything from reduced inflammation and lower heart disease risk to improved brain health. DHA and EPA, two types of omega-3 fatty acids, are particularly important for brain and eye health.

Omega-6 fatty acids, though essential, can contribute to inflammation when consumed in excess compared to omega-3s. This imbalance is common in Western diets and is often associated with several chronic diseases.

Omega-9s, being non-essential, are not as critical but do contribute to maintaining heart health and may help regulate blood sugar levels.

Current Research

Recent human studies have shed light on the benefits of increasing omega-3 fatty acid intake. Research consistently demonstrates that higher consumption of omega-3s, particularly EPA and DHA, is associated with a reduced risk of cardiovascular diseases. These fatty acids help lower triglycerides, reduce blood pressure, and decrease the likelihood of heart attack and stroke. Additionally, there’s growing evidence of their role in mental health, with studies indicating potential benefits in depression, cognitive decline, and other neurological disorders. The anti-inflammatory properties of omega-3s also make them a topic of interest in research on autoimmune diseases.

Omega-3 Fatty Acids and Longevity

The impact of omega-3 fatty acids on longevity is an emerging area of research. These fatty acids are believed to influence aging through various mechanisms, including reducing chronic inflammation, which is a risk factor for many age-related diseases. Studies have suggested that higher levels of omega-3s in the blood are associated with decreased cellular aging markers, such as reduced telomere shortening. Additionally, their benefits for heart and brain health may contribute to increased lifespan and improved quality of life in later years.

Food Sources

To ensure adequate intake of these essential fatty acids, it’s important to know their dietary sources:

  • Omega-3 Fatty Acids: Rich sources include fatty fish like salmon, mackerel, and sardines. Plant-based options like flaxseeds, chia seeds, and walnuts, as well as algae-based supplements, are excellent for vegetarians and vegans.
  • Omega-6 Fatty Acids: These are abundant in vegetable oils (such as soybean, sunflower, and corn oil), nuts, seeds, and processed foods. It’s generally easy to obtain sufficient omega-6 in a typical Western diet.
  • Omega-9 Fatty Acids: Commonly found in olive oil, cashew nut oil, almond oil, avocado, and almonds, these fats are not essential but beneficial for heart health.

Omega-3 Recommendations

The American Heart Association recommends that healthy adults consume 250–500 milligrams (mg) of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) per day (both of which are omega-3 fattty acids). This is roughly equivalent to eating two servings of fatty fish per week.

Personal Experience

Like most Americans my diet is filled with plenty of sources of omega-6 and -9 fatty acids. The struggle is often in getting enough omega-3 fatty acids in my diet. For a long time I used fish oil supplements as my main source of omega-3s but I found high quality omega-3 supplements to be expensive.

Most recently I have been experimenting with different ways to consume canned sardines. A single serving of sardines contains 1463 mg of EPA and DHA, nearly three weeks worth of omega-3s according to the AHA recommendations. My favorite way to eat them is on whole grain toast or crackers.


Omega fatty acids, particularly omega-3, omega-6, and omega-9, play crucial roles in overall health. Omega-3s, with their anti-inflammatory and heart-protective properties, are particularly beneficial and are the focus of ongoing research for their potential in enhancing longevity and preventing chronic diseases. Omega-6s, while essential, should be balanced with omega-3 intake to avoid inflammatory issues. Omega-9s, though not essential, contribute to heart health.

Incorporating a balanced ratio of these fatty acids through a diverse diet rich in fish, nuts, seeds, and healthy oils can significantly impact health and well-being. As research continues to evolve, the understanding and appreciation of these fatty acids in human health and longevity will undoubtedly deepen.


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