Today, most people are eating way too many Omega-6 fatty acids.
At the same time, consumption of animal foods high in Omega-3 is the lowest it has ever been.
A distorted ratio of these polyunsaturated fatty acids may be one of the most damaging aspects of the Western diet.
Omega-6 and Omega-3 fatty acids are called polyunsaturated because they have many double bonds (poly = many).
Our bodies don't have the enzymes to produce them and therefore we must get them from the diet.
If we don't get any from the diet, then we develop a deficiency and become sick. That is why they are termed the "essential" fatty acids.
However, these fatty acids are different than most other fats. They are not simply used for energy or stored, they are biologically active and have important roles in processes like blood clotting and inflammation.
The thing is... Omega-6s and Omega-3s don't have the same effects. Omega-6s are pro-inflammatory, while Omega-3s have an anti-inflammatory effect (1).
Of course, inflammation is essential for our survival. It helps protect our bodies from infection and injury, but it can also cause severe damage and contribute to disease when the inflammatory response is inappropriate or excessive.
In fact, excess inflammation may be one of the leading drivers of the most serious diseases we are dealing with today, including heart disease, metabolic syndrome, diabetes, arthritis, Alzheimer's, many types of cancer, etc.
Put simply, a diet that is high in Omega-6 but low in Omega-3 increases inflammation, while a diet that includes balanced amounts of each reduces inflammation (2).
The problem today, is that people who eat a typical Western diet are eating way too many Omega-6s relative to Omega-3s.
Bottom Line: An Omega-6:Omega-3 ratio that is too high can contribute to excess inflammation in the body, potentially raising the risk of all sorts of diseases.
A good way to figure out what is healthy for humans, is to look at populations that are healthy and don't have all these Western diseases.
Unfortunately, no industrial countries fit that description. Every country that eats an industrial diet gets sick.
Therefore, we must look at non-industrial populations like modern hunter-gatherers.
According to Dr. Stephan Guyenet, who has done a lot of research on non-industrial populations, typical Omega-6:Omega-3 ratios for non-industrial populations ranged from 4:1 to 1:4.
Hunter-gatherers eating mostly land animals had a ratio of 2:1 to 4:1, while the Inuit, who ate mostly Omega-3 rich seafoods, had a ratio of 1:4. Other non-industrial populations were somewhere in between.
All of these populations were in excellent health and didn't suffer from the chronic diseases that are currently killing us Westerners by the millions.
Keep in mind that none of these populations were eating a lot of Omega-6. It is probably a bad idea to eat tons of Omega-6, then a whole lot of Omega-3 to compensate. Having a relatively low, balanced amount of each is best.
Anthropological evidence also suggests that the ratio human beings evolved eating is somewhere around 1:1, while the ratio today is about 16:1 (3)!
Bottom Line: People who eat a non-industrial diet have an Omega-6:Omega-3 ratio of about 4:1 to 1:4, most being somewhere in between. The ratio today is 16:1, much higher than what we are genetically adapted to.
Not only are people eating much less Omega-3, but they are eating large amounts of processed seed- and vegetable oils, which are loaded with Omega-6.
We simply didn't have the technology to process these oils until about a 100 years ago and we have NOT had time to genetically adapt to these high amounts of Omega-6.
You can see on this graph the dramatic increase in soybean oil consumption in the USA, from zero to 11 kilograms (24 pounds) per person per year. This amounted to a total of 7% of calories in the year 1999 - a huge amount (4)!
Soybean oil is currently the biggest source of Omega-6 fatty acids in the USA, because it is really cheap and found in all sorts of processed foods.
In the graph below, you can see how the amount of Omega-6 fatty acids found in body fat stores has increased by more than 200% (3-fold) in the past 50 years alone.
Photo from: Dr. Stephan Guyenet
So the unnatural fats that we are eating are leading to actual changes, both in our body fat stores and cell membranes all over the body. That's a scary thought.
A high amount of Omega-6 in cell membranes is strongly associated with the risk of cardiovascular disease, which makes perfect sense given their pro-inflammatory effects (5):
Another problem with a high Omega-6 intake is the fact that the double bonds in the fatty acid molecules are very reactive.
Fortunately, optimizing your intake of these fatty acids is relatively simple.
Bottom Line: Consumption of vegetable oils high in Omega-6 has increased dramatically in the past 100 years. There is significant evidence that this can cause serious harm.
The single most important thing you can do to reduce your Omega-6 intake is to avoid processed seed- and vegetable oils high in Omega-6, as well as the processed foods that contain them.
These "foods" were only introduced to humans in the past 100 years and they have completely distorted the natural balance of these essential fatty acids.
Here is a chart with some common fats and oils. Avoid all that have a high proportion of Omega-6 (blue bars).
You can see that butter, coconut oil, lard, palm oil and olive oil are all relatively low in Omega-6.
Sunflower, Corn, Soybean and Cottonseed oils are by far the worst. I recommend you avoid these like the plague.
There is more info on cooking oils here: Healthy Cooking Oils - The Ultimate Guide.
Be aware that even so-called health foods can contain vegetable oils. It is crucial to read labels!
Whole soybeans are very high in Omega-6 and should be avoided.
Nuts and seeds are pretty high in Omega-6, but they are whole foods that have plenty of health benefits and are absolutely fine to eat. Many grain-based foods also contain significant amounts of Omega-6.
Bottom Line: The most important thing you can do to reduce Omega-6 intake is to eliminate processed vegetable oils from your diet, as well as processed foods that contain them.
Animal foods are the best sources of the preformed Omega-3 fatty acids, EPA and DHA.
One problem today is that animals are usually fed grain-based feeds with soy and corn.
Some conventionally raised meats like chicken and pork are particularly high in Omega-6. If you want to bring your intake of Omega-6 down as much as possible, then it makes sense to choose the leaner portions of those meats.
It is also best to buy pastured or Omega-3 enriched eggs, which are much higher in Omega-3 compared to eggs from hens that were fed grain-based feeds.
By far the best and healthiest way to increase your Omega-3 intake is to eat seafood once or twice per week. Fatty fish like salmon is a particularly good source. Wild caught fish is best, but even farmed is better than no fish at all.
However, do some research on the product you are buying and the contamination levels in the area where it is farmed.
If you eat a lot of conventionally raised meats and/or don't eat much seafood, then consider taking a fish oil supplement. Cod liver oil is best, because it is also loaded with Vitamin D and Vitamin A.
There are some plant sources of Omega-3, like flax and chia seeds. However, these contain a type of Omega-3 called ALA. Humans are inefficient converters of ALA into the active forms, EPA and DHA (23).
For this reason, animal sources of Omega-3 like fish and grass-fed animals are best.
It's important to realize that this is a long-term process.
Most people are storing immense amounts of Omega-6 fatty acids in their body fat stores and it can take years to get rid of them.
This is a simple guide to optimize your balance of the Omega fats:
- Avoid vegetable oils high in Omega-6 (and the processed foods that contain them).
- Eat plenty of Omega-3 rich animals, including something from the sea at least once or twice a week.
- If needed, supplement with an Omega-3 source like fish oil.