Omega-3 essential fatty acids are often described as the "good" essential fatty acids, while omega-6 essential fatty acids are often described as the "bad" essential fatty acids.
Whether either kind of fatty acid is good or bad for your health, however, depends on balancing omega-6 and omega-3 fatty acids, making sure you get the right amounts of each.
Chemical and Functional Differences Between Omega-3 and Omega-6
Both omega-3 and omega-6 fatty acids are polyunsaturated fatty acids.
In chemical terms, this means that they have carbon atoms that could receive additional bonds to other kinds of atoms in a chemical reaction.
In an omega-3 essential fatty acid, the double bond is at the third carbon in the chain of carbons that makes up the molecule.
In an omega-6 essential fatty acid, the double bond is at the six carbon in the chain.
Ratio of omega-3 to omega-6 is critical for optimum health
The differences in where the double bonds lie make differences in the kinds of hormones the body makes from the fatty acids. Omega-3 fatty acids are turned into the hormones that stop inflammation. Omega-6 fatty acids are turned into the hormones that start inflammation.
Both functions are essential to human health. The problem usually is the omega-3 to omega-6 ratio.
The Modern Diet Provides a Lot More Omega-6 than Omega-3
Omega-6 fatty acids are a lot more common in food than omega-3's. Omega-6's are abundant in meat, especially sausage and hamburger. They are abundant in eggs, butter, lard, and bacon fat.
Omega-6's are also found in most plant oils. Some plant oils, such as corn oil, safflower oil, canola oil, sesame oil, and peanut oil, contain only omega-6's, and no omega-3's.
Even the plant oils that are used to supply omega-3 essential fatty acids, such as walnut oil and flaxseed oil, contain large quantities of omega-6's. The relative abundance of omega-6's compared to omega-3's keeps our bodies in a state of constant inflammation.
That's not necessarily a bad thing if you live in a slum with open sewers and none of your food is refrigerated. Your body may need to be constantly on alert to stop infection.
But if you have the luxury of living in modern comfort with modern sanitation, the energy your body otherwise would put into fighting infection may be turned into destruction of healthy tissues. That's the problem behind a tremendous number of the "diseases of modern civilization".
You Need Omega-6's, Just Probably Not as Much as You Get
Ideally, the body's omega-3 to omega-6 ratio would be about 2 to 1, more omega-3 than omega-6.
Actually, the diet's omega-3 to omega-6 ratio is 1 to 10 to 1 to 30, or 20 to 60 times too much omega-6. It's not that omega-6 essential fatty acids are inherently bad. The problem is that we get far too much of them.
We consume too much Omega-6 fat
How can you cut back on your omega-6 consumption?
If you eat meat, consider eating grass-fed beef rather than grain-fed beef. Grass-fed beef contains about half as much omega-6.
High-DHA eggs also help correct the omega-3 to omega-6 ratio, and if you happen to live in Australia, kangaroo meat is unusually high in omega-3's.
Vegans, vegetarians, and meat eaters alike benefit by including acai berry, chia seed, flaxseed, butternuts, Persian walnuts, hempseed, and seaweed in the diet as often as possible.
But if you are starting with a ratio of 1 to 30 that you need to get down to 2 to 1 in the opposite direction, then you will probably need to go on a lower-fat diet and take an omega-3 supplement. Both fish oil and microalgae are terrific sources of omega-3's.
- Griffin BA (2008). "How relevant is the ratio of dietary n-6 to n-3 polyunsaturated fatty acids to cardiovascular disease risk? Evidence from the OPTILIP study". Curr. Opin. Lipidol.19 (1): 57-62.
- Willett WC, WC (2007). "The role of dietary n-6 fatty acids in the prevention of cardiovascular disease.". J Cardiovasc Med 8: Suppl 1:S42-5.