This blog follows on from an earlier blog on the different types of omega 3, how to get it in your diet and what to look for in a supplement.
You have probably heard omega 3 is good for you. Let’s take a look at some of the reasons why.
Some functions of omega 3 in the body
The following are some of omega 3’s functions in the human body. Please note, this list is not comprehensive, and ‘lipids’ is the group name for the many different types of fats.
-After adipose tissue, our brain is the organ richest in lipids. Around two thirds of the weight of the brain is accounted for by phospholipids. This means a large proportion of our brain is literally made of fat. DHA (decosahexaenoic acid), a type of omega 3 fatty acid found in marine and animal sources, is one of the lipids that make up the structure of the brain. The brain grows rapidly in utero and after we are born, so it makes sense that pregnancy, infancy and childhood are crucial times for getting enough omega 3 in both the mother’s and the baby’s diet.
-Myelin, the insulation on our nerves in the Central and Peripheral Nervous Systems, is largely made of lipids. Fatty myelin is important for protecting and insulating nerve fibres and increasing the speed of nerve impulse transmission, helping the brain communicate with the body and vice versa. Studies in rats and humans have found that the process of myelination is accelerated and supported by omega 3, from childhood to adulthood.
-The photoreceptors in our eyes’ retina are partially made from DHA.
-Omega 3 fats form part of the cellular membrane (outer boundary of the cell) of cells found throughout our body. Having structurally kinky, polyunsaturated fats like omega 3 in the cell membrane keeps it supple and allows nutrients to enter the cell and wastes to exit. This means our cells can more efficiently carry out processes of survival and renewal and maintain homeostasis, among their many other life-sustaining functions.
-Studies have shown omega 3 lowers blood triglycerides (fat levels in the blood), which reduces the risk of atherosclerosis (hardened, narrowed arteries) and thus coronary heart disease, and arterial and kidney diseases. Lowering blood triglycerides also reduces the risk of stroke and possibly cancer.
-Essential fatty acids make prostaglandins, which are substances in the body that have regulating effects. Different essential fatty acids make different prostaglandins. Let’s look briefly at the series 1, 2 and 3 prostaglandins (PGEs).
PGE2s, made from arachidonic acid (an omega 6 fatty acid), typically encourage the body to initiate inflammatory responses such as blood vessel constriction and blood platelet clumping. When our bodies are injured by trauma or substances, such a response is a welcome part of the healing process. However, PGE2s can trigger unwanted chronic, inflammatory processes that are not occurring in response to injury. Excessive levels of PGE2s have been found in colitis (inflammation in the large intestine), dermatitis (skin hypersensitivity) and glomerulonephritis (kidney inflammation). High levels of PGE2 may be linked to high consumption of meat and meat products.
In contrast, PGE1s and PGE3s are anti-inflammatory in the body and are used for repair and healing processes in the digestive, immune and reproductive systems, heart, arteries, skin, neural circuits, and more. PGE3s are made from omega 3 fatty acids, and PGE1s are made from dihomogamma-linolenic acid (an omega 6 fatty acid*), which can be metabolised from gamma-linolenic acid found in Evening Primrose and Borage oils. PGE3 also has a modulating effect on inflammatory PGE2.
(*If you’re reading the part about PGE1s and wondering, ‘Isn’t omega 6 meant to be bad for us?’, the fact is that some omega 6 is necessary in the diet. The issue is that most modern diets contain too much omega 6 and very little omega 3. Omega 6 is typically obtained from vegetable oils used for cooking and in commonly eaten packaged goods such as many breads, crackers, noodles, cakes, cookies, oatcakes, milk substitutes, desserts, spreads, dips, pasta sauces, pre-made sauces, etc.)
From the examples above, we can see that omega 3 is needed for both the structure and healthy functioning of body organs and systems, and that it supports overall health by keeping cell membranes supple and through its anti-inflammatory effects. This underscores the importance of getting enough omega 3 in the diet, because the body cannot make it.
Health conditions omega 3 may help heal
Scientific evidence on the health benefits of omega 3 has so far been suggestive rather than conclusive. This is largely because more methodologically robust studies need to be done to duplicate results before firm conclusions can be drawn. In addition, more studies involving larger sample sizes (i.e., a larger number of people) conducted over longer time periods could give more accurate results.
Another reason the evidence on the health benefits of omega 3 is currently suggestive rather than conclusive is that conducting scientific research – especially clinical trials of people taking dietary supplements such as omega 3 – costs a lot of money. Therefore, a desire to research nutritional medicine needs to be met with adequate research funding, and these two factors don’t always line up.
Even so, omega 3 has been found in a number of studies to show promise in reducing the symptoms of:
It has also been found to reduce the risk of:
On a personal note, I have experienced a reduction or cessation in the following health conditions and symptoms after long-term supplementation of omega 3 (both flaxseed oil and fish oil). I was also taking magnesium and herbal preparations at the same time, and had made some big lifestyle changes.
Bloating and gas
In conclusion, omega 3 is needed for important structural and functional roles in our brain, eyes, nerves, cells and possibly other tissues and organs, and it plays an important role in reducing inflammation, which can be a factor in so many mental and physical illnesses. Furthermore, the ongoing research into omega 3’s therapeutic applications shows promise, especially for mental/neurological illnesses. Yet for many of us, our modern, industrialized diets have moved away from rich sources of omega 3 such as seafood and wild meats. And foods high in omega 6 are now consumed by many people on a daily basis.
To prevent and treat illness, both the biochemical actions of omega 3 and the research on its therapeutic effects indicate that we should consider getting more omega 3 in our diet, both from food and supplements. You can read more on food sources of omega 3 and what to look for in a supplement here.
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