Omega-6 vs. Omega-3 Fatty Acids: What You Should Know
Many are familiar with the popular omega-3 fatty acid found in fish oil, but few have heard of omega-6. So, what is omega-6, and is it good for you?
Not all fats are created equal: Saturated vs unsaturated. Essential vs unessential. Healthy vs unhealthy. The hard part is knowing which fats are good for you and which you should avoid. Along those lines, let’s compare omega-3 fatty acids to omega-6 fatty acids, with an eye toward balance.
Both omega-6 and omega-3 fatty acids are considered PUFAs: polyunsaturated fats. Chemically, PUFAs are simply fat molecules; they are typically liquid at room temperature but start to turn solid when chilled.
PUFAs are much healthier to consume than saturated fats or trans fats because they can help reduce bad cholesterol levels, which in turn lowers your risk of heart disease and stroke.
Furthermore, like omega 3s, omega-6s are considered “essential” fatty acids. That is, the human body requires them for good health, yet cannot make them on their own. Both omega-3 and omega-6 are important in the normal functioning of all tissues in the body.
Is Omega-6 Good for You?
Omega-6 fatty acids are found in leafy vegetables, seeds, nuts, grains, and vegetable oils. They stimulate skin and hair growth, maintain bone health, regulate metabolism, and maintain the reproductive system. When properly balanced with omega-3s, omega-6s are excellent for your health.
In particular, consuming the omega-6 fatty acid GLA (gamma-linolenic acid) has been shown to have positive health benefits. GLA is abundant in rare oils such as black current, the herb borage, and hemp oil. Once ingested, GLA is converted to a substance called DGLA that fights inflammation.
Clinical trials have shown that GLA:
- Helps patients with arthritis by reducing symptoms and the need to take NSAIDs (non-steroidal anti-inflammatory drugs).
- Is commonly used for treating skin conditions such as systemic sclerosis, psoriasis, and eczema.
- Reduces high blood pressure.
- Has been linked to increased bone density and reduce bone loss. (See our post “Osteoporosis -3.0? What Your T-Score Means for Your Bone Health.“
- Improves symptoms and reduces inflammation in certain eye conditions.
- In diabetics, helps diabetic neuropathy by improving nerve conduction velocity leading to improved blood flow and reduce tingling of the lower extremities.
- Improves gaseous exchange in patients with acute lung injury.
- In breast cancer patients, improves the effectiveness of tamoxifen, reduces side effects, and increases the therapeutic response.
- Reduces menopausal symptoms of hot flashes as well as decreases PMS symptoms.
OMEGA FATTY ACIDS: LEARN MORE HERE
To learn more about omega-3, omega-6, and omega-9 fatty acids and their benefits, see these University Health News posts:
GLA Supplementation
The reaction of GLA to DGLA is very slow and can be restricted by alcohol use, stress, smoking, saturated and trans-fatty acid intake, and deficiencies of magnesium, vitamin B6, and zinc. Thus, consuming GLA supplements along with certain nutrients (including magnesium, zinc, and vitamins C, B3, and B6) will help promote the conversion of GLA to DGLA.
GLA supplements in the form of black currant oil and borage oil are often delivered in gel caps. Additionally, spirulina (often called blue green algae) contains GLA. Be sure to speak to your physician to determine the most effective dose for your condition.
Omega-6 and Inflammation
Despite the health benefits of GLA, most other omega-6 fatty acids are actually pro-inflammatory, meaning they can have a deleterious health effect by promoting inflammation in the body. And, chronic inflammation has been linked to a plethora of chronic illnesses including diabetes, heart disease, Alzheimer’s disease, and cancer, to name a few.
Omega-3 Supplementation
There are three major types of omega-3 fatty acids that are ingested in foods and used by the body:
- Alpha-linolenic acid (ALA)
- Eicosapentaenoic acid (EPA)
- Docosahexaenoic acid (DHA)
Most of the ALA consumed in the diet comes from plant sources such as flaxseed and other nuts and seeds. Once eaten, the body uses certain vitamins, minerals, and genetically controlled enzymes to convert ALA to EPA and then to DHA.
EPA and DHA can also be consumed directly. The highest concentrations of EPA and DHA are found in cold-water fish such as salmon, tuna, and herring. EPA and DHA are the two types of omega-3 fatty acids that serve important roles in cell signaling, gene expression, inflammatory processes, and other bodily processes fundamental to health. In other words, it is EPA and DHA, rather than ALA, that perform essential functions in the body.
One popular claim is that your body will automatically convert other omega-3 oils into exactly the amount of EPA and DHA it needs, as long as you provide it with enough omega-3 oils along with the proper vitamins required to assist in the synthesis. One of the important vitamins needed for EPA and DHA synthesis is vitamin B6. If people just consumed adequate vitamin B6, they would efficiently convert the ALA from other omega-3 oils into EPA and DHA and they wouldn’t need to take fish oil, so the claim goes.
But the truth is that conversion of ALA from other omega-3 oils into EPA and DHA is dependent on much more than vitamin B6. Niacin, vitamin C, zinc, and magnesium are needed for the conversion, too.
But that’s only a small part of the story. In fact, scientists still don’t have the full conversion picture totally figured out. However, they have discovered that genetics, age, gender, and—perhaps most important—the other fats in your diet all play important roles in how much EPA and DHA can be synthesized.
Consider these factors, all of which iInfluence your body’s ability to convert ALA to EPA and DHA:
- Other dietary fats. Vegetable oils high in omega-6 fatty acids, such as canola oil, compete for the same compounds that ALA from flax oil needs to convert to EPA and DHA, and the omega-6s win out. Not only that, but omega-6s also inhibit the incorporation of DHA and EPA into your body’s tissues. So the more omega-6 oils you consume, the less EPA and DHA you can make from flax, and even what you can make is blocked from being utilized.
- Gender. Human studies show that males and females differ in their ability to synthesize EPA and DHA from ALA. In particular, women have a higher capacity than men to synthesize DHA from ALA. The studies suggest that estrogen stimulates, whereas testosterone inhibits, the conversion. Thus, women consistently have higher DHA levels than men.
- Age. How old you are appears to make a difference in how well you can synthesize DHA, in particular, from ALA. In recent animal studies, researchers found that the older rats get, the less DHA they can synthesize. Since DHA is the fatty acid incorporated into the brain, researchers believe “its reduced synthesis may be deleterious to brain function.”
- Genetics. Genetic variability in the genes that control the synthesis of the long-chain omega-3’s EPA and DHA is common. Certain variations of these genes have been found to be directly associated with people’s EPA and DHA levels. It wasn’t until quite recently that researchers discovered just how important these tiny variations in genes can be to EPA and DHA synthesis.
In summary, the question of what the best omega-3 supplement is should be put to rest. Although ALA can be used for EPA and DHA synthesis, studies have found that this pathway is limited in humans and varies between individuals based on genes, sex, age, and intake of other fats and nutrients.
So far, no human studies have shown that intake of vegetarian omega-3 sources (ALA) plus certain vitamins, like vitamin B6, leads to optimal levels of EPA and DHA inside the body’s cells and tissues. Therefore, direct dietary intake of omega-3 fats rich in EPA and DHA through food or supplements is the most beneficial.
Omega-6 vs. Omega-3 Ratio
Most Americans consume far too many omega-6 vs. omega-3 fatty acids because they’re abundant in popular cooking oils, including corn, safflower, peanut, soybean, cottonseed, sesame, and sunflower. Having this overabundance of omega-6 fatty acids actually does us harm, promoting inflammation instead of decreasing it. To counteract this, omega-6s must be regulated by the anti-inflammatory omega-3 fatty acids.
In one study, researchers hypothesized that the over-consumption of omega-6 fatty acids to omega-3 fatty acids has paralleled the significant increase in the prevalence of overweight and obese adults. The researchers noted that in the past three decades, the intake of omega-6 fatty acids in the Western diet has increased, while the intake of omega-3 fatty acids has decreased. The result: a ratio of as much as 20:1 (or even higher) in the consumption of omega-6 vs. omega-3. The researchers emphasized the key to reversing the obesity epidemic is to promote a proper fatty acid ratio balance.
Thus, the real take-away here is to make sure you’re getting the proper ratio of omega-3s to omega-6s in your diet. Researchers agree that the optimal omega ratio should be between 2:1 to 4:1. That is, you should consume at least double the amount of omega-3s compared to other fats. The idea is to eat just enough omega-6s to function, but no more, and to balance them with lots of healthy omega-3s.
[1] Omega 6-fatty acids. Retrieved Oct 2017 from University of Maryland Medical System.
[2] Curr Pharm Biotechnol. 2006 Dec;7(6):531-4.
[3] Nutrients. 2016 Mar; 8(3): 128.
[4] Essential Fatty Acids. Retrieved Oct 2017 from Linus Pauling Institute: Oregon State University.
We should get double the amount of omega-3 fatty acids than omega-6 fatty acids, so go easy on popular cooking oils, including corn, safflower, peanut, soybean, cottonseed, sesame, and sunflower, in which omega-6s are abundant. On the other hand, leafy green vegetables are a great source of omega-6s.
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