Omega-3s and Omega-6s: The Basics
In my clinic, I often discuss omega-3 and omega-6 essential fatty acids with my patients. I’m passionate about educating people about how these compounds affect your body and your health.
Essential fatty acids defined…
The body can make most of the fats it needs to function. But certain fats—known as essential fatty acids (EFAs)—must come from the diet alone. Our bodies don’t have the necessary enzymes to make them. Such is the case with the omega-3 and omega-6 families of fatty acids.
Types of omega-3 EFAs
Within each family of fatty acid, there are specific fatty acids that come from different parts of our food supply. For example, there are a few types of omega-3 fatty acids; the most common omega-3s are alpha linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA).
ALA is found in plants, primarily flaxseeds, chia seeds, walnuts, and their oils. EPA and DHA are called long-chain omega-3 fatty acids because they have 20 or more carbons in their structure. These fatty acids are found in fatty fish such as albacore tuna, herring, salmon, mackerel, sardines, and trout. Most scientific and clinical studies carried out to date have examined the effectiveness of these long-chain omega-3s found in fish. Consequently, most scientists who work in this area believe these are the omega-3s that have the greatest anti-inflammatory and brain-protective benefits.
ALA is a plant-based precursor to EPA and DHA, meaning your body in some cases can convert it into EPA and DHA. However, some research has shown that this conversion is not all that effective, and credible studies indicate that individual humans have dramatically different capacities to carry out this conversion. So to be safe, most studies indicate that you are better off getting your omega-3s from fish rather than plant sources.
Types of omega-6 EFAs
There are also several commonly found omega-6 fatty acids that include linoleic acid (LA), gamma-linolenic acid (GLA), and arachidonic acid (AA). LA is by far the most common fatty acid found in the human food supply. It is a primary fatty acid found in cooking oils, including vegetable, corn, canola, peanut, soybean, safflower, and sunflower. GLA is in less common oils—mainly borage, black currant seed, and evening primrose. AA is found in red meat, eggs, and poultry products.
The proper omega-6:omega-3 ratio
Do we need both omega-6s and omega-3s in our diet? The short answer is, yes, we do. Our body requires both of these fatty acids for proper growth, immune response, repair, and brain development.
However, omega-6 and omega-3 fatty acids have very different functions. Omega-6 fatty acids are the precursors of several molecules that cause inflammation (pro-inflammatory), which we now know is the primary driver of most human diseases. In addition to inflammation, omega-6 fatty acids impact blood clotting and cell growth.
In contrast, the omega-3 fatty acids—and especially the long-chain omega-3s - reduce inflammation (anti-inflammatory) and blood clotting and are critical for brain development and function. When both families of fatty acids are in balance, good health results.
But herein lies the problem.
The standard American diet is very high in omega-6s, particularly LA. In the past several decades there has been a rise of LA-enriched cooking oils and processed foods, so our intake of omega-6s has skyrocketed. In fact, the amount of omega-6s we consumed 50 years ago represented about 1.5 percent of our calories. Today, it has increased to a whooping 7-10 percent. There is no single nutrient in the modern Western diet that has increased so dramatically over the past 50 years as omega-6 fatty acids.
Since omega-6 fatty acids are converted to pro-inflammatory molecules, several studies suggest that this high omega-6 (and, comparatively speaking, low omega-3) intake is increasing our risk of systemic inflammation and inflammatory diseases— Cancer, Alzheimer’s, heart disease, diabetes, arthritis, and asthma, to name a few.
Today, the ratio of omega-6 to omega-3 fatty acids in the Western diet is typically 15 to 1 or greater. Ideally, the ratio of omega-6 to omega-3 fatty acids should be closer to 4 to 1, and optimally 1 to 1. But with vegetable oils and processed foods so common in the standard Western diet, even the most diligent dieter tends to consume way more omega-6s than necessary. This imbalance both reduces the amount of omega-3s in circulation and in tissues, and overrides the powerful and important benefits of omega-3s that you do get in your diet.
To tip the scales in favor of anti-inflammatory omega-3s, you need to limit processed foods and vegetable-based oils, while at the same time consuming more of the omega-3 rich foods as listed in my anti-inflammatory diet. And as an extra insurance policy, I often recommend an omega-3 supplement every day.
Omega-3s DHA and EPA
Benefits of EPA
There is still confusion, even among experts, as to the individual roles of omega-3 fatty acids - EPA and DHA - especially given the fact that EPA can be converted to DHA. That being said, much of the data supports the role of EPA as a potent anti-inflammatory and anti-clotting compound.
How does this work? Well, there is a family of inflammatory compounds, collectively known as eicosanoids, derived from the omega-6 fatty acid arachidonic acid. EPA lessens the production of these eicosanoids and their resulting inflammation in a number of important ways.
First, EPA inhibits the enzyme that produces arachidonic acid. Second, EPA impedes the release of arachidonic acid from cell membranes (where it is stored) and its metabolization once it is released. Without this release and metabolism, your body can not make eicosanoids. The result is lower risk of the inflammation that would have been caused by all that arachidonic acid going to eicosanoids.
What about blood clotting? Circulating cells called platelets are critical in causing your blood to clot. When platelets are activated, they aggregate and cause clots. If these clots occur in particularly sensitive regions of your body, they can lead to a heart attack or stroke. EPA reduces platelet activation, an early step in platelet aggregation to help to reduce clotting. One study found that EPA was superior to DHA in decreasing platelet activation, a precursor to blood clotting.
While the anti-inflammatory and anti-clotting properties of EPA are instrumental in many areas of health, you can’t discount EPA’s partner, DHA…
Benefits of DHA
The other omega-3, DHA, is most highly concentrated in the eyes and brain. It’s crucial for proper brain development and function and also helps maintain strong cellular structure and membranes.
DHA is vital for infant and child brain and nervous system development, as well as visual function. In older children, high DHA levels have been shown to improve learning ability, while deficiencies have been linked to learning problems and ADHD. And in adults, some studies have shown that DHA helps protect against cognitive decline and Alzheimer’s disease.
Low levels of DHA have also been found to decrease function of the retina—the part of the eye that captures what you see and transmits those images to the brain. But robust DHA within the eye helps keep tissues porous and enhances nerve transmission, both important for proper eye function.
In addition, DHA helps with heart disease by lowering blood pressure and triglycerides and increasing beneficial HDL cholesterol. One study also found that DHA, more than EPA, helped to prevent heart failure.
Which Should You Take?
You might read other articles or studies that tell you to choose EPA over DHA if you want to reduce inflammation, and DHA over EPA if you want to prevent brain diseases.
Which should you take? I believe evidence indicates the answer to this is both. EPA and DHA both have powerful health promoting properties and work together synergistically in the body, which amplifies their beneficial effects.
For example, even though DHA is thought to be the “brain protective” compound, EPA is associated with prevention of mental health disorders like depression and ADHD as well as brain traumas such as concussions. So you really need a good balance of both to reap their full health benefits.
I recommend an omega-3 formulation every single day that contains both compounds, with confidence that this is helping the heart, brain, and entire body.
Know Omega 6 Sources & Limit High Omega 6 Foods in Your Diet
The best way to reduce your Omega 6 to Omega 3 Ratio is to increase consumption of certain omega 3s by eating fish containing high levels of omega 3s EPA and DHA, and by consuming a premium quality omega 3 fish oil supplement. In addition, it is recommended to follow an anti-inflammatory diet, to learn the leading omega 6 sources and limit high omega 6 foods from your daily diet.
Below is a list of oils high in omega 6, best to limit or avoid:
Omega 6 Sources
Oils (per tablespoon)
Safflower Oil
Grapeseed Oil
Wheat Germ Oil
Corn Oil
Cottonseed Oil
Soybean Oil
Vegetable Oil
Sunflower Oil
Omega-6 Fat
(% of total fat)
75
70
55
54
52
51
58
66
Linoleic Acid
(milligrams)
10,149
9,470
7,450
7,280
7,020
6,940
7,850
5,410
Ratio of Omega-6
to Omega-3 Fats
77:1
947:1
8:1
46:1
234:1
8:1
8:1
180:1