We often hear that Omega-3 fatty acids are health promoting, Omega-6 fatty acids are bad for us, and that the ratio of these two fats in our diets is way off. Should we be concerned?
Nutritional Biochemistry
It can be valuable to understand the biochemistry behind our diets. As a dietitian, I studied these processes for years in order to provide clients with helpful ways to manage illness or discomfort with the foods they eat. But it is possible to focus too much on the nutrients, or the biochemistry of food, and not enough on the diet as a whole.
I think that’s what’s happening in the case of Omega-3 versus Omega-6 fatty acids.
In the past, I’ve found it helpful to take a step back, in an effort to take a step forward, and truly understand how to better apply nutrition research to our everyday food choices. And I think we’ll find that practice to be useful in this instance, because the take home message on these fatty acids is actually much simpler than we have been made to believe…
First of all, what is a fatty acid?
Fatty acids are the building block of the fat we eat and the fat that is in our body. More technically, it’s a hydrocarbon chain with a methyl group (or the omega) made up of one carbon and three hydrogen atoms.
Omega-3 and Omega-6 are proud members of the PUFAS or polyunsaturated fatty acids (not the next boy band), named aptly for having more than one carbon-carbon double bond in the backbone of the molecule. In comparison, saturated fats have no double bonds, allowing them to pack together tightly. This is why saturated fats are typically solid at room temperature (animal fats, for example).
What are essential fatty acids?
In the nutrition world, when something is labeled “essential” it simply means humans must ingest it to have it. Omega-3’s and Omega-6’s are essential to the human diet, because our bodies cannot sufficiently produce them.
What does the number next to “Omega” mean?
When we see “Omega-3” this is an example of a PUFA with its first double bond located off the carbon in the third position away from the omega. Omega-6 has its first double bond off of the sixth carbon in the backbone, sixth from the omega.
What are Omega-6 Fatty Acids?
Omega-6 is required for hair and skin growth, carbohydrate metabolism, and reproductive performance to name a few. Linoleic acid is probably the most commonly referenced, but there are a few.
Depending on what we eat, there could be a little or a lot of Omega-6 fatty acids in a given food. Interestingly, most fat in food will be a mix of saturated and unsaturated fats as well as a mix of the types of omega fats. Walnuts, for example, contain both Omega-3 and Omega-6 PUFAS, as well as some saturated fat.
Other common sources of Omega-6 include safflower, tofu, egg, hemp, and soybean and corn oil, as well as pumpkin seeds. Sources of Omega-6, such as as canola oil for example, are also used in processed food items such as crackers or other packaged foods.
What are Omega-3 Fatty Acids?
Omega-3’s are essential for brain tissue and vision development, cell integrity, and to maintain heart health and blood clotting. The three types are alpha-liniolenic acid (ALA) in plants such as walnuts, flax, and chia, as well as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) found in algae and fish.
ALA found in plant sources can theoretically convert to Omega-3 fats, but it’s more efficient to consume EPA and DHA directly from ocean sources noted above. For those who don’t eat seafood or algae, an Omega-3 supplement can be considered in consultation with a physician.
Which is better: Omega-3 or Omega-6?
The message we have consistently heard over the years is that Omega-3’s are good for us, and Omega-6’s cause inflammation. There are a few reasons, or theories behind this.
It is argued that linoleic can change into arachadonic acid (which is part of many of the molecules that promote inflammation) or compete with Omega-3 for elongation and desaturation. And while the theory makes biochemical sense, humans have different cell types with different abilities to metabolize, and do not operate in such regimented ways.
In fact, research has shown that Omega-6 fatty acids are associated with a lower incidence of cardiovascular disease. This is consistent with The American Heart Association’s assessment, that “despite theoretical concerns regarding omega-6 PUFA and inflammation and oxidative stress, there are no compelling epidemiologic or clinical trial data to suggest that omega-6 PUFA are proatherogenic” (or plaque forming).
What about Omega-6 and processed foods?
Anything that even comes near a processed food item is typically vilified on principle. One could argue safflower oil is a healthy part of our diet, but if it’s an ingredient on the back of a package, it’s guilty by association. Meaning, research more accurately suggests there’s nothing wrong with Omega-6 fatty acids in whole foods, but that when it’s in a cookie box it loses credibility.
It is not sound reasoning to suggest that Omega-6 fatty acids are found in processed foods, so therefore they will cause inflammation. It is more accurate that a diet rooted in processed foods does not provide added health benefits, regardless of which fatty acids are present. One nutrient doesn’t make or break a healthy diet over time.
What about the Omega-3:6 ratio?
This theory makes sense…in theory. If you eat a higher amount of Omega-3, it helps tamp the possible inflammation Omega-6 could cause, if we believe this is indeed true. But there is no consensus on what this ratio should be, and it would likely be different for each individual.
Not to mention, in practicality it is not possible to accurately calculate a daily omega ratio intake because we don’t have enough information provided on our food labels, and even fresh foods and seafood vary in their fat content depending on where they’re sourced, and how it’s transported.
Even if we somehow accurately calculate the ratio, is this the crux of what matters? Meaning, what if we consumed very little of both omegas, but the ratio of Omega-3 to Omega-6 still hit the mark? Is that better than eating more Omega-3 and more Omega-6?
KEY TAKEAWAYS
Omega-3 and Omega-6 fatty acids are both essential to the human diet because our bodies can’t make enough of them. Incorporating a wide variety of fats in our diets is beneficial to help cover all the bases.
One is not better or more important than the other; however, the benefit of either increases when eaten as part of a whole food (like fish, seeds, or nuts) as opposed to always choosing processed foods.
There is no perfect ratio of Omega-3 to Omega-6 fatty acids, and everyone has their own unique needs.
In the meantime enjoy an anchovy or two each week – you got this!
Great explanation Emily. Thank you!
Thank you, Christina!