Lipids (1) – Omega 3 and 6:
Introduction:
For most people, it seems to be very clear that vegetable oils are beneficial for health and that saturated fats, on the contrary, are bad. Once again, we are faced with half-truths.
There is a great difference between what we are told that science says, and what science actually suggest, and this difference has mostly been based on convenience.
In the blogs about lipids, we’re going to dive deep into research to find out what science suggest about lipids, their composition, dangers, how the saturated fat dogma came to be, and how much truth is in what we are told about cholesterol.
Composition:
The oils and fats that we consume are composed of three types of fatty acids, saturated fatty acids, monounsaturated fatty acids, and polyunsaturated fatty acids in different proportions. These proportions determine whether a lipid is solid (fat) or liquid (oil) at room temperature.
The intention of these blogs is to be able to determine according to the studies, which are the healthiest lipids and which are the most adequate proportions of these three fatty acids for The Balance of health.
Essential polyunsaturated fatty acids Omega 3 and Omega 6:
Among the polyunsaturated fatty acids, we have two that are essential. They are called essential, because the body does not produce them and therefore, to enjoy optimal health, they must be obtained from the diet. But this does not mean that you have to eat them in excess and from any source, since like all polyunsaturated fatty acids, they have a great capacity to oxidize (a topic that we will develop in future blogs) and for this reason, they must be obtained only from real unprocessed foods.
Omega 3, Omega 6 and inflammation:
Omega 6 fatty acids are directly involved in inflammatory processes.
The vegetable Omega 6 linoleic acid, is used in the biosynthesis of prostaglandins (inflammatory response) and is also the precursor of arachidonic acid, the animal version of Omega 6.
Arachidonic acid is part of the fatty acids contained in the phospholipids that form the membrane of cells involved in inflammation. In fact, the involvement of arachidonic acid in inflammation is so significant that the pharmaceutical industry designed anti-inflammatories that block this pathway.
That said, it is also necessary to mention that the studies in humans regarding whether omega 6 consumption causes inflammation in healthy individuals or not, is controversial. But what we do know is that Omega 6 inhibits the anti-inflammatory potential of omega 3, suggesting that they tip the balance toward inflammation (1).
One of the characteristics of inflammation is the production of eicosanoids derived from omega 6 (prostaglandins, thromboxanes, leukotrienes and other oxidized derivatives).
Omega-3s not only decrease the production of these eicosanoids, but also decrease inflammation through anti-inflammatory mediators called resolvins, alter the expression of inflammatory genes, and also decrease the production of inflammatory cytokines and reactive oxygen species (2), in other words, Omega 3s are essentially a cocktail of anti-inflammatory processes.
The inflammatory response is necessary for health, but chronic inflammation is associated with many dysfunctions including cardiovascular disease, thrombotic stroke, insulin resistance, cancer, autoimmune disease, depression and psychosis, as it has the potential to damage each body organ (3), which is why some experts believe that inflammation is the cause of all diseases (4).
If we take into account that a high consumption of omega 6 has the potential to inhibit the anti-inflammatory cocktail of Omega 3 that we have just mentioned, maintaining a balance between these two fatty acids seems to be a smart preventive measure.
Even without consuming vegetable seed oils (which have exaggerated amounts of linoleic acid), the modern diet has a large amount of those omega 6 and very little or no omega 3. For this reason, if we want to maintain a balance, we have to pay attention not to consume too much Omega 6 and also, consume more Omega 3, since in a normal diet, it is practically impossible to have an overconsumption of them.
(Note: With the pollution problem that we currently have in our oceans, it is also worth mentioning that the foods rich in omega 3 that are consumed, should also be low in mercury like sardines, mackerel or beef brains)
What about vegetable Omega 3?
Without criticizing any dietary trend, we have to understand that any nutrient, is more bioavailable in its animal version and Omega 3s, are no exception.
While it has been published many times in the media that plant-based omega-3s alpha-linolenic acid (ALA) are effective in maintaining a good level of Omega 3, the truth is that first, they have to become the animal version EPA and DHA in the liver.
The problem is that normally only 5 to 10% of ALA can be effectively converted into DHA or EPA (5), which may explain why the proportions of EPA and DHA in plasma are lower in vegetarians and vegans than in carnivores (6).
ALAs may have some health benefits, but probably has nothing to do with their conversion to DHA or EPA, since for the most part, ALAs do not fulfill the biological activity associated with these animal versions (7).
(Note: There is a vegetable DHA version found in algae.)
(TakeAway: Omega 6 polyunsaturated fatty acids may be essential in the diet, but they should always be consumed in their natural state and apparently, this consumption should be compensated with a good supply of Omega 3, ideally of animal origin.
As it is practically impossible to consume too many Omega 3 of animal origin in a normal diet, special attention must be paid to include them.)
In the next blog, we will analyze the potential danger of oxidized polyunsaturated fatty acids.
References:
1 – Omega-6 fatty acids and inflammation.
2 – n-3 polyunsaturated fatty acids, inflammation, and inflammatory diseases.
3 – The molecular mechanisms of chronic inflammation development.
4 – Leading Integrative Medicine Institute Reveals the Single Unifying Cause of All Disease.
6 – Long-chain n-3 polyunsaturated fatty acids in plasma in British meat-eating, vegetarian, and vegan men
7 – Fish consumption, fish oil, omega-3 fatty acids, and cardiovascular disease.