Omega-3 & Omega-6 Fatty Acids: Their Role and Relationship

In the world of nutritional science, omega-3 fatty acids are frequently praised for their anti-inflammatory effects. Nutritionists recommend consuming fish, nuts, seeds, avocados, and other healthy sources of fat to get these special omegas; doctors prescribe omega-3 supplements to increase that intake even more. Why? Because omega-3 fatty acid status has shown to be tied to conditions related to inflammation, like heart disease, cancer, and autoimmunity.

Just looking at omega-3 status however, doesn’t cover it. What really matters is the omega-6 to omega-3 ratio. Both these fatty acids are essential, meaning they have to be consumed through diet, with omega-3s considered to be anti-inflammatory and omega-6s considered to be pro-inflammatory. Now, this isn’t the whole picture, both are necessary for normal physiologic function, but they need to be in harmony with each other.

The Western style of eating, especially the Standard American Diet, is excessively high in omega-6 fatty acids, but very low in omega-3s, leading to an unhealthy ratio. Human physiology evolved under a ratio of about 1:1 These days, that ratio is more around 20:1, omega-6 to omega-3. The inflammatory downstream effects of omega-6 fatty acids dominate, resulting in increased risk of disease. (1).

The Role of Omega-6 Fatty Acids:
Omega-6 fatty acids are commonly found in vegetable oils, processed foods, and animal products like meat and dairy. Though they are not exclusively metabolized into pro-inflammatory molecules, they are more likely to be. The dominant pathway, starting with linoleic acid, results in the formation of arachidonic acid. From here, pro-inflammatory leukotrienes as well as series 2 prostaglandins are formed. (2)
These molecules are potent mediators of thrombosis (blood clotting) and inflammation. This is why heart disease, along with acute events like myocardial infarction and stroke, are the most commonly discussed outcomes of a poor diet, aka a diet with an unhealthy omega ratio. But, heart disease isn’t the only potential issue. To understand this though, omega-3 fatty acids need to be taken into account. (1).

The Role of Omega-3 Fatty Acids:
Omega-3 fatty acids, on the other hand, are found in flax seeds, pumpkin seeds, walnuts, green leafy vegetables, and fish. The metabolic pathway in this case starts with Alpha-linolenic acid, leads to eicosapentaenoic acid and docosahexaenoic acid, ultimately ending with series 3 prostaglandins, which are anti-inflammatory. (2).

Because of this anti-inflammatory role, regular consumption of food rich in omega-3s has been associated with a low incidence of disease, including atherosclerosis, diabetes, obesity, and inflammatory conditions such as IBD or asthma. (1).

“The Western style of eating, especially the Standard American Diet, is excessively high in omega-6 fatty acids, but very low in omega-3s, leading to an unhealthy ratio.”

The Ratio:

All that aside, what determines whether the pendulum swings towards a pro-inflammatory state or an anti-inflammatory state, at least when it comes to essential fatty acid status, is the ratio between the two. As mentioned previously, a high omega-6 to omega-3 ratio is associated with cardiovascular disease, but more and more conditions are starting to be linked to an unhealthy ratio.

For one, asthma has now been linked to a high omega-6 to omega-3 ratio. A study done in 2019 looked at 135 children with diagnosed asthma and evaluated the severity of their symptoms in comparison to their diet, specifically their intake of fatty acids. They demonstrated that higher omega-6 levels were associated with increased asthma severity, including morbidity (3). Another study, reported in 2020, found that prenatal polyunsaturated fatty acid status could be related to the risk of the child subsequently being diagnosed with asthma, specifically when they had an elevated omega-6 to omega-3 ratio (4). Though more research is warranted, it is possible that dietary change and potentially supplementation with omega-3 fatty acids could therefore modulate atopic disease risk and symptom severity.

Another avenue of study has linked some psychological conditions with essential fatty acid status. For example, in 2017 a cross-sectional study found that a higher omega-6 to omega-3 ratio at baseline predicted mood disorders in high risk individuals over a 7-year follow up (5). In addition, another study performed in 2019 associated low omega-3 status, alone or in combination with high omega-6 status during pregnancy, increased the risk of developing postpartum depression. They concluded that management of an omega-3 deficiency may be a safe and cost-effective strategy for prevention of this condition (6).

With the omega-6 to omega-3 ratio being related to inflammation, and therefore so many conditions, it is of great significance to evaluate in almost all patients. With that in mind, a solid understanding of essential fatty acid status can be determined by looking at diet, but that doesn’t always provide the whole story. An individual’s metabolism, genetics, gender, weight, age, and other lifestyle factors can play a role in fatty acid metabolism and status. Therefore, it is also useful to evaluate the various omega-3 and omega-6 fatty acids via bloodwork. (7)

With a blood analysis of these fatty acids, lifestyle and dietary factors can easily be modulated to balance this ratio. This reduces the risk, and in some cases severity of disease, especially those related to inflammatory status.

Lyfecheck offers comprehensive omega-3 and omega-6 testing. For more information visit www.LyfeCheck.com or email support@lyfecheck.com.